Geosciences doi: 10.3390/geosciences16050185

Authors: Jade Moreira João Luiz Nicolodi Miguel da Guia Albuquerque Breno Mello Pereira Raíssa Magnan Scorsatto

This study assesses the comparative performance of two geotechnologies for shoreline monitoring—Unmanned Aerial Vehicle (UAV) surveys and CoastSnap citizen-science imagery—at Guarita Beach, southern Brazil. The analysis was based on twelve paired monitoring dates distributed over a two-year interval. Shorelines were extracted from the wet–dry line, manually digitized from UAV orthomosaics, and automatically detected from CoastSnap images with subsequent quality control. Shoreline change was quantified in the Digital Shoreline Analysis System (DSAS) using the Shoreline Change Envelope (SCE) and the Linear Regression Rate (LRR). The SCE showed the highest equivalence between methods, with a mean difference close to zero (−0.14 m) and no evidence of systematic bias. For LRR, values derived from CoastSnap tended to be lower than those derived from UAVs (mean difference = −2.14 m year−1), although without statistically significant divergence at the adopted significance level. The results demonstrate that the agreement between CoastSnap and UAV data depends directly on the metric analyzed: SCE was more robust for inter-method comparison, whereas LRR was useful for medium-term trend interpretation but more sensitive to uncertainty propagation. Overall, CoastSnap did not replace UAV surveys, but it proved to be a valuable complementary tool for expanding temporal coverage in coastal monitoring programs.

Geosciences doi: 10.3390/geosciences16050184

Authors: Ali Al Janabi Camelia Knapp Ziyad Albesher Mohammad A. Abdelwahhab Mahmoud Leila Ahmed A. Radwan

In the northern Norwegian North Sea, the Lower Paleogene post-rift succession constitutes an underexplored interval with considerable potential for stratigraphic petroleum plays. Nevertheless, predicting its subsurface prospectivity remains hindered by persistent uncertainties in facies architecture, depositional heterogeneity, and reservoir quality. To address these uncertainties, the present study integrates relative geologic time (RGT)-based seismic stratigraphic interpretation, spectral decomposition, sedimentary facies analysis, and litho-saturation assessment, primarily constrained by seismic and well-log datasets, to evaluate the Paleocene post-rift Lista Formation in the northern Norwegian North Sea. The results reveal the presence of Paleocene mass-transport deposit (MTD) complexes associated with axial lobe sandstones of submarine fan systems. These MTD complexes exhibit pronounced vertical and lateral facies transitions into low-density turbidites, debrites, and hemipelagic drapes, together forming an effective stratigraphic framework for hydrocarbon entrapment. Although the Lista submarine-fan sandstones are relatively thin, typically ranging from a few centimeters to decimeters in thickness, they display favorable reservoir characteristics. Litho-saturation analysis indicates preserved porosity and low water saturation (<20%), supporting their potential as effective hydrocarbon storage intervals. Distal fan-lobe sandstones, despite their limited thickness, show encouraging reservoir quality, whereas thicker low stand systems tract (LST) accumulations and time-equivalent carbonate mound complexes appear to have developed within more proximal structural domains. This proximal-to-distal facies organization reflects the dynamic interaction between tectonically inherited accommodation space and sediment-routing pathways during the early Paleocene. Overall, the findings highlight the significant petroleum prospectivity of the Paleocene post-rift succession in the northern Norwegian North Sea. The stratigraphic juxtaposition of sand-prone submarine-fan lobes against hemipelagic sealing intervals, combined with heterogeneity imposed by syn-rift structural inheritance, generates a highly favorable architecture for stratigraphic trapping. More broadly, the integrated workflow presented here enhances the predictive mapping of subtle stratigraphic traps within post-rift successions and provides a robust framework for reducing exploration uncertainty in analogous basins.

Geosciences doi: 10.3390/geosciences16050183

Authors: Alexander Radulov Yordanka Donkova Nikolay Nikolov Marlena Yaneva Konstantin Kostov Ivan Alexiev

The Devene fault system, a major strike–slip structure at the boundary between the Balkan Range and the Moesian Platform in NW Bulgaria, remains a subject of debate regarding its Quaternary activity. This study investigates the shallow expression of the fault at two representative sites, Tri Kladentsi and Beli Breg, using high-resolution electrical resistivity profiling to differentiate tectonic deformation from climatically driven landscape evolution. At Tri Kladentsi, resistivity profiles confirm a steeply dipping structural boundary within the Miocene bedrock, juxtaposing limestone against sands. The overlying 25 m thick loess cover, however, remains sub-horizontal and undisturbed. Likewise, at Beli Breg, the complex architecture of stacked channel sequences and tributary deposits at the Ogosta River confluence reveals no identifiable fault displacement. Our results suggest a high degree of morphological mimicry, where asymmetric river valleys produced by selective erosion and differential loess accumulation superficially converge with tectonic signatures. The long-term left-lateral slip rate is estimated at 0.14–0.19 mm/yr based on a 20 km Miocene offset. Nevertheless, the lack of modern surface rupture indicates a deceleration of the fault slip rate and a transition to a buried fault top during the Quaternary. These findings necessitate a re-evaluation of regional seismic hazard assessments, because the absence of continuous surface traces physically constrains the maximum earthquake potential.

Geosciences doi: 10.3390/geosciences16050182

Authors: Yao Qu Caide Lin Hai Liu Xiangtai Liu Xu Meng Shangyang Zhang Zixin Yin Hesong Hu

The imaging quality of electrical resistivity tomography (ERT) crucially depends on the electrode array configuration. Although the symmetrical optimized ‘Compare R’ (CR) method improves computational efficiency, restricting the search to the symmetrical data set inherently limits the imaging accuracy. To address this limitation, this paper proposes a multi-step optimized CR method that progressively explores both symmetrical and asymmetrical arrays to extend the search space and further enhance imaging accuracy. Numerical experiments demonstrate that the multi-step optimized array yields the highest average relative model resolution (0.646) and structural similarity index measure (0.668), surpassing the symmetrical optimized array (0.615 and 0.630, respectively). Field experiments on pipeline detection confirm that the proposed array accurately identifies the location and geometry of underground anomalies and achieves superior imaging accuracy. Applications in karst cavity exploration further confirm that the proposed array effectively detects the deep karst caves and the bedrock interfaces, as validated by borehole drilling. Additionally, the detection performance of both optimized arrays is evaluated at different depths. The results indicate that the multi-step optimized array preserves anomaly geometry and resistivity more reliably at greater depths, attributed to the accumulation of asymmetrical data points in deep regions, which results in a significantly higher data density.

Geosciences doi: 10.3390/geosciences16050181

Authors: Haiquan Li Huanhuan Wu He Huang Guoqing Wang Zhanlin Ge Ming Liu Di Hao

Permian A-type granites and associated rare-metal mineralization are widespread in the Halajun area, southwestern Tianshan; however, petrogenetic controls on rare-metal enrichment and mineralization remain under-constrained. Here, we integrate zircon and monazite geochronology, whole-rock geochemistry, and zircon Hf-O isotopes from Halajun I and II plutons to constrain the origin of these granites and their metallogenic significance. Zircon U–Pb and monazite ages indicate emplacement at 274–273 Ma, coeval with regional magmatism associated with the Tarim large igneous province. Geochemical signatures—high SiO2, alkali, and rare-earth element (REE) contents, enrichment of HFSE (e.g., Nb, Zr, and Hf), coupled with LILE (e.g., Ba and Sr) depletion—classify these granites as highly differentiated alkaline A-type rocks. Positive εHf(t) values and intermediate δ18O compositions of zircons suggest derivation from partial melting of Neoproterozoic lower crust with input from mantle-derived melts, reflecting significant crust–mantle mixing. Magmatic differentiation, in concert with regional crustal reworking driven by mantle plume activity, produced granites enriched in Nb, Ta, Zr, and REEs, which host the rare-metal mineralization in the region. These results indicate that Permian crustal reworking in the southwestern Tianshan was a driver of high-differentiation magmatism and rare-metal enrichment, highlighting the potential of similar A-type granitic systems in Central Asia for rare-metal exploration.

Geosciences doi: 10.3390/geosciences16050180

Authors: Zhibo Chen Jinduo Gao Wei Huang Ping Hu Xuefeng Tang Zhigang Zhao Banglai Lü

Completely weathered granite residual soil is a weathering-derived, soil-like geomaterial whose shear strength is difficult to characterize using only conventional small-scale laboratory tests. This study evaluated the effects of specimen size and material structure by comparing in situ direct shear tests, conventional laboratory direct shear tests on undisturbed and remolded specimens, and large-scale laboratory direct shear tests on remolded specimens with box sizes of 150, 200, and 250 mm. The results show that undisturbed specimens exhibited higher shear strength than remolded specimens, indicating a clear structural contribution. With increasing specimen size, cohesion decreased from 41.2 to 31.4 kPa, whereas the friction angle increased from 35.3° to 40.6°. Compared with the conventional undisturbed test, the in situ tests yielded lower cohesion but higher friction angles. These results indicate that both size effect and structural disturbance significantly influence the interpretation of shear strength parameters in completely weathered granite residual soil. For engineering design in weathered-granite terrains, strength parameters derived from larger specimens or in situ tests are likely to be more representative than those obtained from conventional small-scale laboratory tests.

Geosciences doi: 10.3390/geosciences16050179

Authors: Jozef Bódi Peter Vajda Pavol Zahorec René Putiška Juraj Papčo Roman Pašteka José Fernández

Underground water flow in karst areas and changing water levels due to extreme rain can lead to the creation of caverns and sinkhole hazards. Such is the historical experience of the Valaská village in central Slovakia. To better understand the current sinkhole threat in the village, we aim to detect shallow caverns using microgravimetry. Our broader objective is to examine the capabilities of the Growth inversion methodology to detect and characterize shallow cave space. In our study, we focus on the benefits and weak points of the Growth inversion approach, which is a free-geometry inversion method based on model exploration and growing source bodies. Since a sole gravimetric inversion produces ambiguous results, we pay attention to the role and setup of the several free user-adjustable inversion parameters of Growth. We examine tuning these parameters for the specific needs of shallow cavity detection. Valaská experienced sinkholes in 1964, 1968 and 2019. That of 1964 is known for a curious loss of a horse sunk into a karst chimney. Our gravimetric work shows that the sinkhole hazard at the exposed lot in Valaská is ongoing despite the mitigation construction measures. The Growth approach proved to be applicable and useful in microgravimetric identification of sinkhole threat and detection of shallow caverns in karst.

Geosciences doi: 10.3390/geosciences16050178

Authors: Vikas C. Baranwal Martin C. Sinha Lucy M. MacGregor Anna C. Maxey Yang Su

Marine controlled source electromagnetic (CSEM) surveys have been proven to be an effective tool in hydrocarbon exploration, principally due to the method’s ability (in the right circumstances) to identify electrical resistivity contrasts between hydrocarbon-saturated and brine-saturated sedimentary units. However, the sensitivity of such surveys decreases in shallow water, for deeper targets, and for targets with limited horizontal extent. In principle, the resolution and sensitivity of a survey can be improved by moving either the transmitting or the receiving dipoles into the sub-surface. We have therefore investigated the sensitivity of Seafloor to Borehole CSEM (sbCSEM) survey geometries, specifically for the case of simplified targets with small lateral dimensions in shallow water areas—including targets whose depth of burial substantially exceeds their lateral extent. The results are encouraging. Neither small target size nor shallow water presents obstacles in principle to the use of this approach. Our models reveal distinct lobes in the patterns of electric field and current density amplitudes around a sub-seafloor transmitting dipole. The shape, positions and amplitudes of these lobes are all strongly modified by the presence of one or more small resistive targets, and they are strongly influenced by the positions of target edges. These effects significantly modify the pattern of electric fields at the seafloor and hence result in good sensitivity for realistic survey geometries. Small targets can be detected by seafloor receivers when the sub-seafloor transmitting dipole is located at some distance laterally outside the targets—leading to potential applications in ‘step-out’ prospecting. The asymmetry of responses at the seafloor from targets that are offset with respect to transmitter location has potential applications in field appraisal, while monitoring of reservoirs during production provides another possible application. Varying the depth of the transmitter down the borehole generates a Vertical EM Profiling (VEMP) survey—analogous to Vertical Seismic Profiling (VSP)—and we demonstrate that this too can have useful applications. Modelling for deeper (3 km sub-seafloor) targets continues to yield encouraging results and suggests that step-out sbCSEM may be effective at depths beyond the detection limit of conventional seafloor–seafloor CSEM.

Geosciences doi: 10.3390/geosciences16050177

Authors: Demin Zhang Fayou Li Zhongmin Zhang Chaonian Si

Recently, a substantial quantity of oil and gas has been discovered in the pre-salt Lower Cretaceous microbialite successions of Brazil’s Santos Basin, thereby prompting a global surge in research related to microbialites. It has been demonstrated that microbial shoal reservoirs yield the highest hydrocarbon production, with optimal reservoir properties, as evidenced by experience in the field of oilfield production. However, as research progresses, it has become increasingly evident that significant heterogeneity exists in both the lithology and physical properties within microbial shoal bodies. In order to address the identified knowledge gap, the present study employs systematic petrological and petrophysical datasets. These include 30-m continuous core samples, thin-section analyses, routine petrophysical tests and mercury injection capillary pressure (MICP) measurements. The aim is to characterize the internal microfacies architecture and reservoir heterogeneity of microbial shoals. It is imperative to ascertain the principal factors that govern the heterogeneity observed in these reservoirs. This critical step is essential for a comprehensive understanding of the subject matter. The results of the study demonstrate that: the Barra Velha Formation microbial shoals in the Santos Basin can be subdivided into three microfacies, which are delineated from base to top. The foundation of the shoal is the shoal base. The rock composition is dominated by the presence of spherulites, with intracrystalline pores functioning as the primary reservoir spaces. The compositional rocks of the shoal flank are poorly sorted microbial debris, with intergranular and intragranular pores formed by penecontemporaneous dissolution. The sedimentary succession of the shoal core is characterized by well-sorted microbial debris rocks displaying multiple shallowing-upward sequences, with reverse-graded textures. The primary storage space is constituted by fabric-selective pores from penecontemporaneous dissolution, though these are subject to local disruption by destructive silicification. Meanwhile, the microbial shoals demonstrate wide porosity (8.8–26.4%, mean 16.8%) and permeability (0.13–839 mD, mean 169 mD) ranges, thus classifying them as medium-porosity, high-permeability reservoirs. The superimposition of microfacies and diagenetic processes gives rise to considerable reservoir heterogeneity. It is evident that the shoal core microfacies exhibits robust energy and substantial grain size, characteristics that facilitate its exposure above lake level during periods of high-frequency lake-level oscillation. This exposure is further compounded by the influence of atmospheric water dissolution, which remodels the microfacies during the quasi-contemporaneous period. The reservoir quality is optimal, exhibiting the highest proportion of large pores. The reservoir properties of the shoal flank are closely followed by medium and large pores, and those of the shoal base are the worst, with micro and medium pores.

Geosciences doi: 10.3390/geosciences16050176

Authors: Jian Xu Haiping Fan Danial Jahed Armaghani

Accurate prediction of blasting-induced peak particle velocity (PPV) is critical for assessing structural damage risk and ensuring safe tunnel construction. This study proposes an AI agent-based Evaluator-Optimizer workflow that automates the model-development pipeline from prepared dataset input through model training, performance evaluation, hyperparameter optimization, and ensemble construction, with limited manual intervention after dataset definition. The framework employs a multi-agent architecture comprising three collaborative agents—an Orchestrator, an Evaluator, and an Optimizer—supported by a large language model (LLM) reasoning layer. The Evaluator agent analyzes model performance across multiple metrics and generates diagnostic insights; the Optimizer agent translates these insights into structured optimization plans; and the Orchestrator coordinates the evaluate-optimize loop and stopping logic. The workflow was applied to a dataset of 102 tunnel blasting events. Nine candidate regression models spanning tree-based, kernel-based, neural network, and regularized linear families were trained and evaluated. The results show that the workflow enables three substantive observations: (i) across five tree-based models the powder factor is the dominant predictor (28.7–50.5% relative importance); (ii) under 50 Monte-Carlo repeated 80/20 splits, KNN and the Voting ensemble are statistically indistinguishable and form the most stable performance cluster, while Gradient Boosting lies within the same cluster with larger variance; and (iii) under nested 5 × 5 cross-validation, the un-leaked R2 for the top models is about 0.84–0.86, which quantifies the small-sample over-optimism that any future PPV study on single 80/20 splits should expect. The study therefore contributes both a portable agent architecture for tabular geotechnical regression and a concrete cautionary result about single-split benchmarking.

Geosciences doi: 10.3390/geosciences16050175

Authors: Aashish Pokhrel Laureano R. Hoyos Xinbao Yu

Soil thermal conductivity is a key parameter in modeling heat transfer, temperature-driven moisture migration, artificial ground freezing, and geothermal systems. However, most existing thermal-conductivity models do not account for temperature effects. This study aims to determine the temperature-dependent thermal conductivity of silty and fine sandy soils at elevated temperatures using a steady-state heat cell method, addressing the limitations of transient probe techniques, which are affected by air voids and heat loss at the needle–soil interface. The experiment employs a heat cell under one-dimensional steady-state heat-transfer conditions, with sufficiently small temperature gradients to prevent temperature-induced moisture migration, and measures the soil’s thermal properties at steady state by indirect temperature and heat-flux measurements using various sensors. The test observations showed well-correlated thermal conductivity readings from steady state and transient probe methods at room temperature. Furthermore, the measured thermal conductivity of the sandy soil demonstrated a near-linear increase with temperature, with the highest dependence at 15.1% and 22.5% saturation for Benbrook (SM) and fine-grained Ottawa (SP) sands, respectively. Several commonly used existing thermal conductivity models were used to fit the measured thermal conductivity. A new thermal conductivity model was developed, incorporating a temperature-dependent correction based on the best-fit model. The proposed model could more accurately capture the increased thermal conductivity of soils with temperature. The findings will significantly improve the modeling of soil-temperature-dependent multi-physics behavior.

Geosciences doi: 10.3390/geosciences16050174

Authors: Joseph Moll David Malone Tiffany Rivera Robert Biek David Hacker Ashley Griffith Michael Braunagel

The late Paleogene White River Group is a post-Laramide sedimentary succession that occurs within Laramide intermontane basins and atop some basement-cored uplifts. Detrital zircon U-Pb dates of tuffaceous sandstones from the uppermost White River Group in eastern Wyoming and western Nebraska yield a maximum depositional age of 23.07 ± 0.46 Ma, which overlaps the emplacement of the Markagunt Gravity Slide in Utah’s Marysvale Volcanic Field at 23.05 + 0.22/− 0.20 Ma. The Marysvale Volcanic Field (~31–18 Ma) lies at the east margin of the Nevadaplano, a longstanding highland in the Sevier Hinterland later dismembered by basin and range extension. Strata both proximal and distal to the Marysvale Volcanic Field show an increase in Marysvale provenance up to the emplacement of the Markagunt Gravity Slide. After emplacement, distal sediment sourcing of Miocene strata in the Great Plains shifted back to older Paleogene volcanic fields farther west in Nevada. This temporal relationship suggests that the collapse of the Marysvale Volcanic Field associated with the emplacement of the Markagunt Gravity Slide forced drainage reorganization and sediment sourcing during the transition from White River to Arikaree Group sedimentation.

Geosciences doi: 10.3390/geosciences16050173

Authors: Hernán Patiño Fausto Molina-Gómez Rubén Ángel Galindo-Aires

Tailings are unconventional geomaterials that require dynamic characterisation due to seismic hazards at several storage facilities. Due to the anthropic origin of these materials, their dynamic properties differ from those reported for natural soils. In particular, the damping ratio is a relevant parameter that controls the dynamic response of tailings storage facilities. It can be estimated using different experimental methods. The objective of this research is to disclose the results obtained through laboratory tests in which the damping ratio was evaluated independently by Half-Power Bandwidth or the free-vibration decay methods. A comprehensive testing plan comprising resonant column tests and free-vibration decay tests was carried out on three types of tailings from the Riotinto mines (Huelva, Spain): Cerro Salomón Sand (CSS), High-Density Sludge (HDS), and Copper Lamas (CL). These tests were carried out under different effective consolidation pressures and torsional excitations. The results allowed the establishment of a series of relationships between the testing conditions and the identification of differences between the methods for tailings.

Geosciences doi: 10.3390/geosciences16050172

Authors: Rui Gao Chenxi Zhang Weichen Gao Guorui Feng Xiao Huang Xueming Zhang Hong Guan

Rock fracture mechanics and the associated energy-release behavior play a key role in ensuring safe extraction in underground coal mining. Hydraulic fracturing generates prefabricated fracture networks in competent rock strata, thereby modifying fracture propagation patterns and reducing the failure resistance of the strata. In this study, standardized three-point bending tests were conducted to investigate the fracture behavior of pre-cracked sandstone specimens with different crack morphologies, quantities, and spacings. New crack initiation occurred mainly at the midspan in specimens containing horizontal prefabricated cracks, whereas inclined prefabricated cracks promoted crack initiation from the crack tips. Although horizontal crack length did not exhibit a clear monotonic effect on load-bearing capacity, the overall capacity decreased with increasing crack density or decreasing crack spacing. Vertical cracks further reduced load-bearing performance, particularly at relatively small crack spacings. The strain response exhibited a non-monotonic relationship with horizontal crack parameters, increasing first and then decreasing with increasing crack length and spacing, while showing a positive correlation with vertical crack spacing. Dissipated energy was negatively correlated with prefabricated crack angle, accounting for 92.65%, 89.10%, and 94.03% of the total input energy. With increasing crack length, the proportion of dissipated energy first increased and then decreased, with values of 92.65%, 90.77%, 92.52%, and 96.13%. Energy dissipation decreased with increasing horizontal crack spacing but increased with vertical crack spacing. Numerical simulations further showed that both horizontal and vertical fractures generated by ground fracturing promoted timely strata failure, while vertical fractures were more effective in facilitating overburden fracture propagation and reducing the bearing capacity of the rock strata and advance coal body by more than 13%. These findings provide a mechanistic basis for the control of thick and competent hard-roof strata.

Geosciences doi: 10.3390/geosciences16050171

Authors: Leila Abbasian Pushpinder S. Rana Alison Leitch Stephen D. Butt

Non-destructive characterization of electromagnetic (EM) wave propagation properties in drill cores is gaining prominence as a foundation for reliable geophysical inversion, improved rock-physics modeling, and increasingly data-driven mineral exploration workflows. Lab-based rock characterization requires benchmarks that link the density, elastic, electrical, magnetic, and EM properties of studied cores to lithology and mineralization, enabling more accurate interpretation of geophysical data. This study develops a robust high-frequency EM (HFEM) wave velocity measurement technique and incorporates it within a standardized non-destructive framework validated across multiple mineral systems in Newfoundland and Labrador, Canada. The developed method derives EM velocities from two-way travel time through drill cores positioned above a metallic reflector, supported by finite-difference time-domain simulations to optimize antenna frequency and test geometry. A repeatable signal-processing workflow was implemented to enhance reflection picking. Results reveal systematic EM velocity contrasts among host rocks and oxide or sulfide-bearing systems, with oxide-rich and massive sulfide intervals exhibiting higher density, elevated conductivity and susceptibility with strong EM attenuation. The integrated dataset shows that conductivity and magnetic susceptibility significantly influence EM velocity response and detectability limits. The proposed multi-parameter benchmark enables enhanced discrimination of lithological and mineralization controls in mineral exploration workflows and supports more accurate time–depth conversion in HFEM geophysical and ground-penetrating radar (GPR) methods.

Geosciences doi: 10.3390/geosciences16050170

Authors: Béla Raucsik Andrea Varga Olga Piros Andrea Szuromi Korecz Elemér Pál-Molnár

The Middle Triassic Bulz Dolomite Formation in the Apuseni Mountains (Romania) lacks detailed microfacies documentation and paleoenvironmental reconstruction, leaving its regional correlation unresolved. This study aims to describe the microfacies and fossil assemblages of the Bulz Dolomite to reconstruct the Anisian depositional environment and establish regional stratigraphic links. More than twenty outcrop samples were analyzed using conventional microfacies analysis, UV/VIS-fluorescence, and cathodoluminescence microscopy. Results reveal that early, fabric-retentive dolomitization preserved microbial boundstones, dasycladalean algae (Teutloporella peniculiformis, Physoporella pauciforata), and benthic foraminifers (Hoyenella sinensis), indicating shallow-marine, peritidal, and restricted lagoonal environments. The multiphase diagenetic history involves early reflux dolomitization from hypersaline brines, burial recrystallization forming nonplanar and saddle dolomites, and late-stage meteoric calcite cementation. The diagnostic fossil assemblage firmly constrains the formation to the Anisian age. Consequently, the Bulz Dolomite shares compelling lithological, diagenetic, and biostratigraphic affinities with the Szeged Dolomite Formation in the basement of the southeastern Pannonian Basin, demonstrating the presence of a unified, expansive evaporitic carbonate shelf extending across the Tisza Megaunit along the Neotethyan passive margin.

Geosciences doi: 10.3390/geosciences16050169

Authors: Jiawen Chen Changbao Yang Liguo Han Shiqin Yang

This study investigates how solar and geomagnetic driver selection affects 24 h-ahead global ionospheric vertical total electron content (VTEC) prediction under different geomagnetic conditions. A four-step feature selection strategy involving importance evaluation, redundancy elimination, physical interpretability prioritization, and performance validation was developed to identify five key drivers from candidate solar and geomagnetic factors. Using global ionospheric maps provided by the Center for Orbit Determination in Europe (CODE) from 2014 to 2018, a non-overlapping 90-day temporal block scheme was adopted to reduce the risk of temporal information leakage. Six ablation experiments were conducted to compare the predictive performance of different driver combinations. The results show that the full-factor configuration selected by the proposed strategy achieved the most favorable overall performance among the tested combinations, although the global-average improvement relative to the baseline remained modest. The optimal driver combination varied with geomagnetic disturbance level, and the contribution of external drivers showed clear latitudinal dependence. In addition, the full-factor configuration yielded a more balanced global error distribution and was associated with slower error accumulation over the 24 h horizon. These findings suggest that physically guided driver selection is useful for constructing more physically meaningful driver combinations and for improving long-horizon prediction stability within a unified ConvLSTM-based framework.

Geosciences doi: 10.3390/geosciences16050168

Authors: Nada Bouferdous Eric Guilbert Sylvie Daniel

The introduction of multibeam echosounders has marked a turning point in bathymetric data acquisition, providing precise and detailed digital bathymetric models. These instruments not only enhance our understanding of underwater terrain dynamics but also reveal the presence of complex sedimentary structures, such as submarine dunes. Dunes play an important role in the preservation of the environment but can also be obstacles to safe navigation, requiring dragging operations. Hence, it is important to detect them from bathymetric models. Although information about these dunes has numerous applications, their identification methods remain poorly automated. This paper aims to leverage deep learning to develop a segmentation method for submarine dunes. Several challenges must be overcome. Dunes are complex objects with irregular, highly variable shapes, while bathymetric data are noisy and lack detailed information. Furthermore, in the fluvio-marine context, no labeled datasets exist for training purposes. Starting from a small pre-labeled dataset, this paper proposes a systematic approach to train a Mask R-CNN network. First, data augmentation techniques are applied to expand the dataset significantly and introduce meaningful variations. By relying on transfer learning with a carefully selected pre-trained backbone, feature extraction is optimized, reducing training time while enhancing model performance. The adaptation of the Mask R-CNN model to our submarine dune segmentation task has led to a significant improvement in detection performance, with a pixel-level F1-score reaching 89%. Additionally, the mean Average Precision has exceeded 50%, demonstrating the model’s effectiveness in identifying and delineating dunes despite their varied shapes and blurred contours. These results confirm the relevance of our approach for achieving more reliable dune segmentation in a complex fluvio-marine environment.

Geosciences doi: 10.3390/geosciences16050167

Authors: Shuang Geng Zhanyu Wei Xi Xi Yating Deng Da Zhang Chenyu Ma Honglin He

The Daliangshan Fault Zone (DLSFZ) constitutes a key segment of the Xianshuihe–Xiaojiang Fault System (XXFS) and exerts fundamental control on the eastward extrusion of the Sichuan–Yunnan Block (SYB). In this work, we present new slip rate determinations at three key sites (Tekoujiagu, Yeer, Damulo) along its middle-southern segments using UAV-based high-resolution topography and OSL dating. Results yield late Quaternary slip rates of 4.5 ± 1.4, 3.7 ± 1.1, and 5.5 ± 1.0 mm/a, respectively. Combined with previous data, the slip rate is 1.5–3.1 mm/a in the northern segment, 1.36–4.3 mm/a in the middle and 2.5–4.5 mm/a in the southern segment, which exhibits a spatial pattern of “higher in the south, lower in the north, with transition in the middle”. Temporal evolution suggests increased slip rates from the Late Pleistocene to Holocene. These characteristics indicate that the DLSFZ is a heterogeneous deformation system, where strain focusing on the southern segment reflects the block’s eastward escape constrained by the rigid Sichuan Basin (SB). Thus, the DLSFZ, especially its southern segment, serves as a key structure regulating crustal extrusion at the southeastern margin of the Tibetan Plateau (TP).

Geosciences doi: 10.3390/geosciences16050166

Authors: Félix Díaz Nhell Cerna Rafael Liza Bryan Motta

Radon has long been investigated as a potential earthquake precursor, yet its interpretation remains challenged by meteorological, hydrological, and instrumental variability that can generate apparent departures unrelated to tectonic processes. This review synthesises how artificial intelligence is being applied in radon-based earthquake precursor research, with particular emphasis on anomaly detection and the evaluation of radon seismicity associations. Following a PRISMA-guided workflow, Scopus and the Web of Science Core Collection are searched and screened for eligibility, yielding 26 journal articles, most of which are concentrated in a limited number of tectonically active regions. Across the reviewed literature, a consistent pattern emerges: AI is used primarily to model the expected radon background, while candidate precursors are identified mainly through threshold-based indices derived from residuals or concentration ratios rather than through explicit earthquake-probability outputs. Although pre-seismic departures are reported repeatedly, this review shows that the evidence base remains constrained by heterogeneous operational definitions of anomaly, strong methodological variation across studies, a predominant emphasis on background goodness-of-fit instead of alarm-level performance, and limited use of time-ordered validation. These findings highlight both the promise and the current limitations of AI-enabled radon analysis. The main contribution of the field so far is not direct earthquake prediction but a more structured framework for separating potential tectonic signals from non-seismic variability. In this sense, the review provides an important methodological synthesis for future research and shows that more reproducible and operationally useful radon monitoring will depend on clearer anomaly definitions, stronger confounder control, more rigorous temporal validation, and more standardised performance reporting.

Geosciences doi: 10.3390/geosciences16040165

Authors: Yue Cai Shiwu Liu Liangliang He Xiang Guo Guijuan Li Lei Yang Shaoni Wei

Sandstone of the Lower Cretaceous Luohe Formation is the main water inrush source in the Binchang Mining Area in the southwestern Ordos Basin. Its sedimentary environment and provenance features are critical for local coal development and safe mining. The Luohe Formation at Xiaozhuang Coal Mine comprises three vertical members: the lower member dominated by coarse- to medium-grained sandstones, the middle member mainly composed of fine-grained sandstones, and the upper member characterized by interbedded fine- to medium-grained sandstones and sandy conglomerates. This subdivision newly identifies a complete hydrodynamic evolutionary cycle of depositional environments from high-energy to low-energy and back to high-energy conditions. Integrated petrographic observations and analyses of major and rare earth elements first confirm that the tectonic affinity of the Luohe Formation progressively shifted from a passive continental margin to an active continental margin, accompanied by a corresponding transition in sediment provenance from the North China Craton to a magmatic arc source region. Trace element compositions precisely indicate that the Luohe Formation was deposited in a fluvial freshwater environment under hot, arid, and oxidizing conditions, thus providing new constraints on the paleoenvironmental evolution of the region.

Geosciences doi: 10.3390/geosciences16040164

Authors: Noura Lkebir Xiongwei Zeng Long Cheng Zhijun Niu

This study fills a knowledge gap in the distribution of the Upper Cretaceous dinosaur tracks in central China by examining two newly discovered tracksites near Xiakou village (Nanzhang County) and Jiuxian town (Yuan’an County), Hubei Province. Eleven Isolated tracks were analyzed to identify the ichnofauna assemblage. Morphometric analysis indicates the presence of tridactyl and rounded morphologies. The tridactyl tracks are consistent with a small-sized theropod and ornithischian ichnofauna, whereas the rounded shape remains ichnotaxonomically indeterminate. These tracks are the first reported dinosaur ichnite from central China at this age. Despite limited preservation, this research highlights how extromorphological factors influence track morphology, a key issue in ichnological studies. Overall, it contributes new data on the presence of dinosaur ichnofauna in China during the late Mesozoic.

Geosciences doi: 10.3390/geosciences16040163

Authors: Xingping Yin Yuqiang Jiang Yifan Gu Yuegang Li Zhanlei Wang Xiugen Fu

The marine shale of the Longmaxi Formation is the main layer for shale gas exploration and development in the Sichuan Basin. That said, the pore structure in the Longmaxi shale is strongly heterogeneous, and how these pores form and are preserved remains unclear—which limits our understanding of what makes a good reservoir and holds back efficient shale gas development. To investigate the coupling relationship between hydrocarbon generation and pore evolution in marine shale, medium-maturity shale from the Longmaxi Formation in NE Sichuan was collected for thermal maturation experiments. Shale samples and pyrolysis products from different evolutionary stages were obtained for a series of analyses, including gas composition and pore structure. The influence of organic hydrocarbon generation and inorganic diagenesis on the development of shale nanopores was revealed, and a pore evolution model for marine shale was established. The results show the following: (1) The hydrocarbon generation process of medium-maturity marine shale consists of three stages. The maximum methane yield is 362.58 mL/g. (2) As the thermal maturity increases, the quartz content shows a gradual increase, while the content of clay minerals, feldspar, and carbonate minerals decreases. (3) As the thermal maturity increases, pore evolution is observed in four stages: “slow decrease,” “rapid increase,” “relatively stable,” and “slow decrease.” The first stage is characterized by pore reduction dominated by intense compaction. The second stage is dominated by pore expansion driven by mineral transformation and dissolution. The third stage is the pore preservation stage, during which continuous natural gas generation occurs. The fourth stage is characterized by pore reduction, mainly driven by weak compaction. This study has enriched the theoretical understanding of the dynamic evolution of shale pores, providing a theoretical basis for the research on the formation and enrichment mechanism of shale gas and the exploration practice of shale gas reservoirs.

Geosciences doi: 10.3390/geosciences16040162

Authors: Wei Yu Li Gong Jiao Wang Feng Wang Jingchun Tian Jie Chen

Diagenetic anomalies within the Upper Paleozoic coal-bearing strata of the Longdong area, Ordos Basin, represent a complex interplay between thermal maturation and fluid evolution, yet their governing mechanisms remain poorly understood. This study integrates petrographic analysis, X-ray diffraction, vitrinite reflectance (Ro) measurements, and fluid inclusion microthermometry to evaluate the discrepancy between organic thermal maturity and mineralogical diagenetic records. The results indicate that the mudstones achieved high thermal maturity, with mean Ro and Tmax values of 2.3% and 555.1 °C, respectively. However, the associated sandstones exhibit anomalous mineral assemblages, characterized by persistent high levels of illite/smectite (I/S) mixed-layer minerals and authigenic kaolinite, which are inconsistent with the anticipated advanced diagenetic stage. Furthermore, homogenization temperatures (Th) of fluid inclusions are significantly lower than expected, implying a localized suppression of illitization. We propose that this atypical diagenetic trajectory is governed by sluggish fluid–rock interactions in a confined diagenetic environment. Specifically, the dissolution of feldspars during acidic diagenesis provided a localized Al3+ supply, favoring kaolinite precipitation, while the limited availability of reactive feldspar precursors and pore-fluid retention effectively stalled the progression of illitization. These findings demonstrate that reactant availability and reaction kinetics can decouple mineralogical evolution from organic thermal maturation in coal-bearing sequences. This study provides a novel mechanistic framework for interpreting anomalous diagenetic signatures in heterogeneous sedimentary basins, offering significant implications for reservoir quality prediction in deep-seated, thermally mature strata.

Geosciences doi: 10.3390/geosciences16040161

Authors: Qianlong Zhang Wei Deng Ming Su Jinqiang Liang Lei Lu

Natural gas hydrate is a clean energy resource critical for global energy security and low-carbon transition. Understanding its geological accumulation mechanisms is essential for exploration and development. However, the current research on NGH geological accumulation lacks a systematic and quantitative analysis of its global research evolution, hotspots, and frontiers. To fill this gap, this study conducts a bibliometric analysis of 5891 articles (1999–2025) from the Web of Science Core Collection using CiteSpace and VOSviewer to map research trends, contributions, and frontiers. The results show that annual publications followed a three-stage trajectory: slow initiation, rapid growth, and stable development, with key boosts from production tests in Japan (2013) and China (2017). Marine and Petroleum Geology emerged as the most cited journal. China, the United States, and Germany lead research output, with the Chinese Academy of Sciences serving as the central hub (centrality: 0.46). Core researchers such as Jinqiang Liang have established foundational knowledge through highly cited studies on accumulation theory and resource–environment interactions. Research focus has shifted from early resource assessment to controlling factors, and recently toward production technologies and parameter optimization, highlighting a transition from basic to applied research with strong interdisciplinary integration. While bibliometrics reveals structural evolution and hotspots, limitations in data sources and analytical scope remain. Future efforts should integrate multi-source data and deepen content analysis to address unresolved challenges in NGH geological accumulation.

Geosciences doi: 10.3390/geosciences16040160

Authors: Vincenzo Amato Sabatino Ciarcia Cristiano B. De Vita Laura De Girolamo Daniela Musmeci Lorenzo Radaelli Alfonso Santoriello

The viae romanae (Roman roads) were constructed according to precise designs and exceptional engineering techniques, ensuring their strength and durability. They represent an immeasurably important factor in human history. Their impact has been universal, facilitating the movement of people, goods, ideas, beliefs and religions over the centuries. The Via Appia Regina Viarum, built between the end of 4th and 1st centuries BCE, connected Rome to Brundisium, spanning the region of Latium and Apulia. The road initially crossed the coastal plains of the Tyrrhenian Sea (in Latium) before cutting through the reliefs and river valleys of the southern Apennines (in Campania) and finally crossing the regio Apulia et Calabria via Tarentum, to the harbor of Brundisium, along the Adriatic coast. In 2024, the Italian Ministry of Culture proposed the ‘Via Appia Regina Viarum’ for inscription on the Unesco World Heritage List, recognizing its unique and exceptional testimony to Roman civilization. Later that same year, the nomination was accepted, and today, the Via Appia is part of the UNESCO World Heritage List. A significant contribution to this nomination came from the multidisciplinary studies and research conducted along the Via Appia between the ancient cities of Beneventum and Aeclanum in the Campanian Apennine, including: (1) geoarcheological investigation aimed at identifying the ancient path of the road, which was not well documented in the area between Beneventum and Aeclanum; (2) studies focused on cultural and geological heritage along the road and its surrounding landscapes, enhancing the value of the nomination; and (3) the organization of social and cultural events designed to disseminate scientific findings and raise awareness among scientists, students, local and national administrators, local food and wine producers, and the general public. This paper highlights the pivotal role of geoscience at all stages of the project: from preliminary field surveys and mapping of landforms and lithofacies, to targeted field and geophysical surveys, to archaeological excavation and geoarchaeological consideration, and to the dissemination of new data through cultural events.

Geosciences doi: 10.3390/geosciences16040159

Authors: Floriana Angelone Francesca Martucci Edoardo G. D’Onofrio Filippo Russo Paolo Magliulo

The assessment of the hydromorphological state of a river is fundamental for both correctly evaluating its ecological conditions and planning its restoration. Despite this, there is a critical gap in studies on this topic in Southern Italy, although they are recommended by several EU Framework Directives. This research provides a contribution to filling this gap by assessing the hydromorphological quality of the Middle and Lower Sabato River (Southern Italy), by using the method officially adopted by the Italian Institute for Environmental Protection and Research (ISPRA), named IDRAIM. The method presents the advantage of considering the specific Italian context in terms of channel adjustments and anthropogenic impacts. However, it also considers pre-existing geomorphological approaches developed in other countries that make the method applicable at least in the entire Mediterranean area. To apply the method, in this study, we used data obtained by GIS analysis, remotely sensed data, and field-surveyed data. The study has highlighted that, in the Middle and Lower Sabato R., eight river reaches out-of-fifteen have displayed a “moderate or sufficient” morphological quality, five reaches a “good” morphological quality, while the remaining two reaches have been characterized by a “poor” morphological quality. Functional alterations have seemed to prevail over artificiality and intensity of short-term channel adjustments in conditioning hydromorphological quality. These results will be a key starting point for already planned studies dealing with both the restoration of the Sabato R. and flood hazard and risk assessment.

Geosciences doi: 10.3390/geosciences16040158

Authors: Eli K. Moore Shaunna M. Morrison Amber Hatter

Continental remobilization is a crucial driver of metallogenesis and the formation of ore deposits. Some of the world’s largest mineral deposits of the economically valuable elements tin (Sn), tungsten (W), gold (Au), copper (Cu), lead (Pb), and zinc (Zn) formed during the Mesozoic Era. Additionally, the chemistry and distribution of the elements Sn and W have been investigated in previous studies to understand planetary formation and differentiation processes. These two elements are largely co-located during certain South China Mesozoic metallogenic events but are not co-located during other time periods in the same regions. Here, we investigated the mineral chemistry network similarities and dissimilarities of Sn and W to understand their mineral formation and distribution during the Mesozoic Era and throughout Earth history. Mineral chemistry network community detection analysis and electronegativity associations among mineral constituent elements of Sn minerals and W minerals indicate that the elements have similar chemistry among their oxide minerals. However, Sn forms a much wider range of minerals that also contain S compared to W, which occurs in a limited number of S-containing minerals. The divergent constituent element interactions among S-containing Sn minerals and W minerals reflect the redox sensitivity and importance of oxygen (O) fugacity in Sn mineral formation. Conversely, extensive W mineral deposits are known to form at both high and low O fugacities. The similarities and differences between the mineral chemistry networks of Sn and W reflect the mineral distribution of the two elements in the Sn-W mineralization event from 160 to 139 Ma vs. the Sn–uranium (U) mineralization event from 125 to 98 million years ago (Ma). The mineral chemistry and distribution of Mesozoic Sn and W deposits illustrate the contrasting importance of redox and O fugacity on the mineral formation of different elements, and the dynamic crustal evolution that took place during this period of Earth history.

Geosciences doi: 10.3390/geosciences16040157

Authors: Fanfan Dou Yan Zou Huaixue Xing Hongjie Ma Chaojie Zhen Shiying Yang Yong Hu Haijie Yang

Geological environment evaluation for urban underground space (UGEE) is a critical foundation for optimizing the utilization of urban underground space (UUS) and mitigating exploitation risks. With recent advancements in 3D geological modeling technology, 3D UGEE has emerged as a transformative approach, offering innovative perspectives and technical solutions for rational 3D spatial development and geological risk reduction in subsurface engineering. A core component of the 3D UGEE workflow is the integration of diverse 3D spatial analysis methods, which enable comprehensive extraction of evaluation indices from multidimensional datasets—forming the essential basis for scientifically informed development planning. Focusing on quantitative 3D UGEE, this study systematically investigates the implementation of 3D spatial analysis methods across four key stages: (1) geological condition analysis, (2) evaluation information extraction, (3) 3D comprehensive evaluation, and (4) result analysis. Specifically, five core methodologies are highlighted: (1) 3D spatial statistical analysis, (2) 3D mathematical morphological analysis, (3) 3D surface morphology analysis, (4) 3D spatial distance field analysis, and (5) 3D spatial interpolation analysis. To improve the reliability and objectivity of 3D comprehensive evaluation results, we integrate game theory-based combination weighting with an improved TOPSIS model, which balances the subjectivity of expert judgment and the objectivity of data characteristics while adapting to the 3D block unit data structure, effectively avoiding the bias of single weighting or evaluation models. To validate these techniques, a case study in Hangzhou, Zhejiang Province, is conducted, demonstrating their practical effectiveness in evaluating UUS resources. The findings underscore that advanced 3D spatial analysis methods significantly enhance decision-making precision in UUS planning and risk management, providing a replicable framework for sustainable subsurface development.

Geosciences doi: 10.3390/geosciences16040156

Authors: Alfio Di Giovanni Simone Saltarin Andrea Carigi Carmine Todaro

The management of waste bentonite slurry (WBS) produced during slurry shield TBM excavation involves environmental and operational challenges from the perspective of developing a more sustainable tunnelling construction process. In this study, the potential reuse of WBS as a complete replacement for bentonite in two-component grout formulations used for TBM backfilling is explored. A comprehensive laboratory testing program is conducted, in which the effects of WBS on the properties of two-component grout (unit weight, viscosity, bleeding, gel time, and mechanical strength) are assessed after various curing times, and the outcomes are compared with standard values commonly given in technical specifications. WBS produced from two different commercial bentonites is investigated. The results show that while the first formulation exhibits rapid setting and irregular gelation, the mix derived from the second bentonite demonstrates superior mechanical performance, increasing compressive strength by up to 40%. This enhancement is primarily governed by a physical filler effect, where fine soil particles optimize packing density and refine the microstructure. Consequently, the incorporation of selected types of WBS into a two-component grout could be a practicable approach, since it offers benefits in terms of mechanical performance, although careful mix design would be required to manage workability. This study shows how tunnelling can become more sustainable by reusing excavation waste and transforming it into a useful by-product.

Geosciences doi: 10.3390/geosciences16040155

Authors: Katherine E. Broad Benjamin O. Sadler Peter B. James Skylar L. Hoover Nicholas L. Wagner Don R. Hood

We conducted a paired gravity and seismic survey at Kentland Crater with the goal of investigating its subsurface density structure. Our results show that the complex crater hosts a ~4.5 mGal Bouguer gravity high corresponding to the central uplift. The southeastern portion of the crater structure exhibits a low-gravity annulus at 3.5–4.5 km radius, with an adjacent high that we define as the rim at ~5.0 km radius, implying a 10 km apparent diameter. Passive seismic data is used to characterize the low-density glacial till layer, which blankets the bedrock throughout the study area. The central gravity anomaly persists after removing the gravitational influence of the till layer. Kentland’s large, positive central gravity anomaly is likely due to the removal of the low-density material beneath the original crater floor by extensive erosion via glacial scouring. We therefore suggest that the impact-induced porosity at Kentland Crater was likely confined to the original near-surface (<900 m), which aligns with recent numerical modeling. Due to the wide range of diameter estimates, we conclude that the current geometry of Kentland Crater remains ill-defined. Compiled datasets are provided here for use in future investigations.

Geosciences doi: 10.3390/geosciences16040154

Authors: Amed Bonilla Pérez Nathan Cogné Carlos Alfonso Zafra Mejía

The northwestern Amazonian Craton exposed in eastern Colombia preserves a complex Proterozoic tectonothermal history. In this study, we present new zircon and apatite U–Pb geochronological data from orthogneisses of the Guaviare Complex (Termales Gneiss unit) to constrain the timing of crust formation, metamorphism, and subsequent thermal events. Zircon U–Pb data define a dominant concordant population at ca. 1.30 Ga, interpreted as the crystallization age of an igneous protolith. This age is consistent with Mesoproterozoic A-type magmatism previously recognized in the region and consistent with emplacement under intracratonic extensional conditions, as suggested by previous studies. A limited number of discordant zircon analyses indicate Pb loss and/or partial isotopic resetting between ~1.0 and 0.6 Ga, although no well-defined metamorphic zircon population is identified. Meanwhile, apatite U–Pb analyses from key samples yield consistent lower intercept ages between 633 ± 16 Ma and 543 ± 8 Ma, indicating a widespread Ediacaran thermal disturbance that may have affected the Guaviare Complex, temporally overlapping with alkaline magmatism in the northwestern Amazonian Craton, including the San José del Guaviare Nepheline Syenite. However, alternative mechanisms such as fluid-assisted Pb mobility, regional reheating, or prolonged cooling cannot be excluded. Finally, the combined zircon–apatite dataset highlights the value of multi-chronometer approaches for resolving complex thermal histories in cratonic domains.

Geosciences doi: 10.3390/geosciences16040153

Authors: Elias E. Chikalamo Olga C. Mavrouli Piernicola Lollino

Research on landslides around reservoirs is necessitated to strengthen risk prevention and mitigation, as their occurrence has catastrophic consequences. For reservoir safety assessments, landslide susceptibility analysis is commonly concentrated on single reservoir bank slopes or individual landslides. However, focusing solely on bank slopes and individual landslides gives an incomplete picture of how safe the reservoir is from possible landslide related risks, since landslides from distant slopes can also adversely affect the reservoir in different ways. In this paper, landslide susceptibility assessment was conducted using machine learning models (Gradient Boosting Machine, XGBoost, Random Forest and Ensemble Stacking) in the area around the San Pietro Dam, an earth dam located in Southern Italy, in a region highly prone to landslide hazards. The landslide inventory for the area was used to generate landslide and non-landslide points for model training and testing. The area under curve (AUC) of a receiver operating characteristic (ROC) curve approach was used to evaluate, validate, and compare the performance of the four models. Results indicated that the ROC AUC values of the models ranged from 0.76 to 0.77, with the Random Forest, Gradient Boosting and Ensemble stacking models having AUC values of 0.77. All the models classified about 15–20% of the reservoir basin as highly susceptible to landslides. The generated basin-scale landslide susceptibility maps can be used to prioritize monitoring and maintenance in areas around the dam that have been identified as highly susceptible.

Geosciences doi: 10.3390/geosciences16040152

Authors: Joana Alexandra Ferreira Helena C. B. Martins Maria dos Anjos Ribeiro José Francisco dos Santos

Isotopic disequilibrium during the formation of high-temperature (HT) metamorphic complexes by anatexis during continental collision is a process that deserves intense discussion since it is fundamental to understand the evolution of continental crust. The axial sector of the Iberian Variscan Belt (IVB) is known by the profusion of synorogenic granites that are sometimes clearly associated with the migmatites composing the HT metamorphic complexes. The Pedregal Migmatitic Complex is located in the autochthonous domain of the IVB and is composed of metatexites and diatexites associated to syntectonic two-mica granites. The anatectic process occurred by dehydration melting of muscovite and biotite with the growth of peritectic minerals such as garnet, K-feldspar, and sillimanite in metatexites; and K-feldspar, sillimanite, and hercynite in diatexites reaching the metamorphic peak at 313.3 ± 0.5 Ma. A process of residuum-melt separation during crustal melting is attested by the Pedregal migmatites, giving origin to metatexites and residual diatexites as indicated by field evidence and their geochemical signature. Zircon oxygen isotopes and inherited zircon ages point to the Douro-Beiras Supergroup metasedimentary sequence (Beiras group) as a possible protolith of the Pedregal diatexites. Conversely, the isotopic composition of the diatexites suggests isotopic disequilibrium caused by residual mineral phases (biotite, monazite and garnet).

Geosciences doi: 10.3390/geosciences16040151

Authors: Juan Luis Ccamapaza Aguilar Hebert Hernán Soto Gonzales Sheda Méndez-Ancca Mario Ruiz Choque Luis Enrique Sosa Anahua Renzo Pepe-Victoriano Alex Tejada Cáceres Danny Efrain Baldarrago Centeno Olegario Marín-Machuca Jorge González Aguilera

The geomorphological characterization of coastal–marine environments is essential for environmental management and biodiversity conservation. The objective of this study was to model the geomorphological diversity of the Punta de Coles National Reserve, located in Puerto de Ilo, Moquegua, Peru, using GNSS geodetic receivers, integrating topographic and bathymetric data to continuously represent both the emerged and submerged relief. The methodology involved establishing two “C”-order geodetic control points, implementing a closed polygon with 13 vertices, conducting a topographic survey, and recording bathymetric data along coastal transects extending 1 km offshore using an echo sounder and GNSS positioning. The data were processed in a GIS environment to generate a Coastal–Marine Digital Terrain Model (CM-DTM) with metric resolution. The results showed a total area of 171.451 ha, with elevation variations ranging from sea level to 71.617 m above sea level. Distinct geomorphological units were identified, such as coastal plains (0–5% slope), hills (15–35%), and cliffs (>45%), in addition to 16 rocky islets covering 1.537 ha. In the underwater environment, the model made it possible to identify submerged terraces, slopes, and local depressions down to a depth of −115 m, revealing a continuous transition between the land and sea topography; additionally, areas with a higher susceptibility to erosion and areas of high ecological importance were identified. This study’s contribution lies in the integration of GNSS geodetic data with topobathymetric surveys, which enabled the generation of a high-precision continuous model in an area with limited prior information, establishing a scientific baseline for coastal and marine management and conservation.

Geosciences doi: 10.3390/geosciences16040150

Authors: Suresh Neupane Netra Prakash Bhandary Dericks Praise Shukla

Rain-induced shallow landslides persistently disrupt Nepal’s mountain roads, frequently leading to fatalities, transport disruptions, and economic losses. This study develops physically validated, site-specific rainfall thresholds for the landslide-prone Kanti National Roadway (H37) by integrating empirical intensity–duration (I-D) analysis, antecedent rainfall metrics, and satellite-derived soil moisture data. Using 35 years of rainfall records (1990–2024) and 59 field-verified landslides (2017–2024), we derived a localized I-D threshold: I = 19.37 × D−0.6215 (I: rainfall intensity in mm/h; D: duration in hours), effective for durations of 48–308 h, encompassing short intense storms and prolonged moderate rainfall. The Cumulative Antecedent Rainfall (CAR) method associated most failures with 3-day totals, while the Antecedent Precipitation Index (API) showed superior performance, with a 10-day threshold of 77 mm capturing all events. For physical validation, NASA’s SMAP Level-4 root-zone (0–100 cm) soil moisture data revealed a 1-day lag in response to rainfall; after adjustment, trends matched API saturation predictions and identified an inverse rainfall–moisture pattern before the 11 August 2019 landslide, indicating a potential instability precursor. This integration enhances predictive accuracy, bolsters mechanistic understanding of landslide hazards, and offers a scalable, cost-effective early-warning framework for data-scarce mountain regions, aiding climate-resilient infrastructure in regions with intensifying rainfall extremes.

Geosciences doi: 10.3390/geosciences16040149

Authors: Emmanouil A. Varouchakis Evangelos Machairas Ioulia Koroptsenko Stylianos Tampouris Christos Stenos Michail Galetakis

The growing demand for Critical Raw Materials (CRMs) requires mining practices that align with sustainability and environmental, social, and governance (ESG) principles, while mining training increasingly benefits from advanced digital tools. Virtual Reality (VR) can provide high-resolution site representations that support both interactive learning and data-oriented analysis without operational risk. This study presents a VR-based framework for the quantitative assessment of pit lake rehabilitation using Virtual Excursions (VEs) developed from panoramic imagery and supported by machine-learning correction. High-resolution 360° panoramic images were used to extract geometric characteristics of a rehabilitated pit lake at the LARCO GMMSA Euboea mine site, Greece, including surface area, shoreline length, mean diameter, and maximum diameter. These image-derived estimates were validated against ground-truth data from field surveys and mine-closure documentation. To reduce systematic deviations associated with panoramic image measurements, a supervised multiple linear regression model was applied as a correction step. Validation based on Root Mean Square Error (RMSE) and the coefficient of determination (R2) showed substantial improvement of the corrected estimates relative to the uncorrected image-based measurements. The results demonstrate that panoramic VR imagery can support site-specific quantitative environmental assessment in addition to its educational value. Although the present findings are limited to a single pit lake case study, the proposed workflow provides a structured basis for integrating immersive visualization, image-based measurement, and regression-based correction in post-mining rehabilitation assessment.

Geosciences doi: 10.3390/geosciences16040148

Authors: Spyridon Mavroulis Efthymios Lekkas

This research provides an extensive evaluation of liquefaction induced by earthquakes in the Ionian Islands, specifically Lefkada, Cephalonia, Ithaki, and Zakynthos, through the compilation of a liquefaction inventory and GIS-based liquefaction susceptibility index (LiSI) maps. A total of 49 liquefaction sites from 20 causative earthquakes confirm that liquefaction is a recurrent geohazard in the area, primarily affecting coastal and low-lying areas with unconsolidated post-alpine deposits. The relationship between earthquake magnitude and maximum epicentral distance of observed liquefaction is consistent with global empirical datasets, indicating that moderate to strong earthquakes (Mw = 5.9–7.4) can induce liquefaction at considerable distances. The susceptibility model integrates eleven conditioning variables, classified as geological and geomorphological variables, hydrological indices and optical satellite imagery-derived data, within an analytic hierarchy process (AHP) framework. Lithology, age, and geomorphological unit emerged as the dominant conditioning variables. The LiSI maps confirm the zones previously identified in the inventory. Model validation and sensitivity analysis including confusion matrix components, key performance metrics and ROC analysis in coarser grid sizes demonstrate performance ranging from excellent (Zakynthos) to moderate (Lefkada and Cephalonia), while remaining inconclusive for Ithaki due to data limitations. The model exhibits generally conservative behavior, characterized by high precision and specificity but variable sensitivity, while it is largely stable across spatial resolutions in most cases.

Geosciences doi: 10.3390/geosciences16040147

Authors: Alexandra Mota Joana Alexandra Ferreira Fernando Noronha Helena Sant’Ovaia

Variscan two-mica granites are widespread in the Trás-os-Montes region (NE Portugal), yet their emplacement ages, petrogenesis, and relationship with Variscan deformation phases remain poorly constrained. This study integrates U–Pb zircon geochronology, whole-rock geochemistry, and oxygen isotope data to characterise four peraluminous two-mica granites in the Trás-os-Montes area (Fornos, Carviçais, Fonte Santa, and Bruçó) and to refine their tectonomagmatic context within the Central Iberian Zone. All granites are S-type, ilmenite-series, and derived from reduced magmas, as indicated by their strongly peraluminous compositions, mineral assemblages (muscovite ± biotite), absence of magnetite and presence of ilmenite, and high δ18O values (>11‰), consistent with partial melting of metasedimentary crust. U–Pb ages reveal two distinct magmatic pulses: an older event at ~340 Ma (Fornos and Fonte Santa granites), predating the onset of C3 deformation and likely associated with late C1 crustal thickening to early C2 tectonics, and a younger pulse at ~320–318 Ma (Carviçais and Bruçó granites). These magmatic pulses are linked to contrasting structural controls, with the older granites emplaced within regional-scale antiforms and the younger intrusions localised along structures related to C3 deformation. Together, these results document two discrete crustal melting events separated by ~20 Ma and record a progressive shift from fold-controlled to strike-slip-dominated granite emplacement during Variscan orogenic evolution. Moreover, the study highlights that tungsten mineralisation is preferentially associated with reduced, crust-derived granites emplaced during specific tectonic regimes, providing new constraints for metallogenic models in NW Iberia.

Geosciences doi: 10.3390/geosciences16040146

Authors: Bikash Chaudhary Krishna Kanta Panthi

Unlined pressure tunnels and shafts are widely employed in hydropower projects where the surrounding rock mass is required to sustain the internal water pressure. Their hydraulic stability is governed by complex interactions among the three-dimensional in situ stress state, discontinuity geometry, rock mass properties, and operational water pressure. Conventional deterministic design approaches address these factors implicitly and provide limited information on the likelihood of hydraulic failure mechanisms, such as hydraulic jacking, hydraulic fracturing, and shear slip of discontinuities. This paper presents a probabilistic framework for assessing the hydraulic stability of unlined pressure tunnels and shafts, in which the governing failure mechanisms are explicitly formulated as limit states and key sources of uncertainty are systematically represented. The full three-dimensional stress tensor is rotated onto potential discontinuity planes to evaluate effective normal and shear stresses, and reliability-based methods are employed to quantify probabilities of failure. The methodology is demonstrated through a representative case study of a failed unlined pressure tunnel reflecting typical geological and stress conditions encountered in hydropower projects. The results show that variability in stress orientation and discontinuity characteristics has a strong influence on hydraulic stability and that commonly used deterministic criteria may not fully capture the associated failure risk.

Geosciences doi: 10.3390/geosciences16040145

Authors: Xijiang Wu Hengli Zhou Wenlong Xu Fasheng Miao Lixia Chen Chuncan He Yiqing Sun

As one of the most catastrophic geological hazards globally, landslides exhibit heightened risks due to their increasing frequency, destructive potential, and extensive spatial distribution. The primary objective of this study is to develop an integrated analytical framework to quantitatively evaluate the stability of variably shaped slopes under rainfall infiltration. The core hypothesis is that slope curvature significantly alters infiltration behavior and stress distribution, leading to morphology-dependent failure mechanisms. Employing Green-Ampt infiltration theory coupled with limit equilibrium analysis, we establish stability prediction models for three fundamental slope geometries (linear, concave, convex) under contrasting rainfall regimes (high-intensity vs. low-intensity precipitation). The derived analytical solutions reveal two critical phenomena: (1) progressive downward migration of the saturation front maintaining parallelism with slope surfaces during infiltration and (2) time-dependent stability deterioration following hyperbolic decay patterns. The proposed models are rigorously validated through numerical simulations employing finite element methods, which demonstrate remarkable congruence with theoretical predictions, showing safety factor discrepancies below 5% (ΔFs < 0.05). Particularly, concave slopes exhibit 18–22% faster destabilization rates compared to convex counterparts under equivalent rainfall conditions. The validated models elucidate the spatiotemporal evolution of matric suction and pore pressure distributions, providing quantitative insights into morphology-dependent failure thresholds. These findings advance predictive capabilities for rainfall-induced landslides through physics-based stability criteria, offering critical guidance for terrain-specific early warning systems and mitigation strategies in geohazard-prone regions.

Geosciences doi: 10.3390/geosciences16040144

Authors: Paxton Tomko Cesar Ivan Ovando-Ovando Pierre Boussagol Michel Geovanni Santiago-Martínez Pieter T. Visscher

Methanogens, or methanogenic archaea (MA), are among the most ancient and widely distributed microorganisms, characterized by a unique metabolism that generates methane (CH4) as the terminal product of anaerobic respiration. Their ability to grow and/or survive across a wide range of environmental conditions has made methanogens key contributors to biogeochemical cycles throughout most of Earth’s history. Most importantly, these oxygen-sensitive microorganisms have regulated the climate since the early Archean and impacted biogeochemical cycles throughout Earth’s history by producing the potent greenhouse gas, CH4, while consuming H2, CO2, and small organic molecules. Hence, methanogens are attributed a key role in the start and end of several Proterozoic glaciations and mass extinction events. Their specific roles in the long-term carbon cycle that focus on CH4 production are well-established, but, in contrast, only very few studies report on interactions with CaCO3 and long-term carbon storage. Methanogens evolved early during Earth’s history, likely during the Archaean Eon, in layered benthic microbial communities called microbial mats. When lithified, these mats form microbialites that represent some of the earliest evidence of life in the fossil record, dating back >3.5 Gy. Methanogens are an integral part of contemporary microbial mats and have been identified both in the anoxic and oxic zones of these sedimentary ecosystems; however, their adaptations to apparently unfavorable oxic conditions and their role in the precipitation of carbonate in mats are unclear. In addition to an important role in the evolution of our planet by producing CH4, methanogens may also produce a biosignature that could be relevant for astrobiology research. This review will discuss the diversity, physiology, and ecology of methanogens in detail to clarify their role in some of the major biogeochemical processes and ecological climatic events through the fluctuating environmental conditions on Earth through geologic time.

Geosciences doi: 10.3390/geosciences16040143

Authors: Tao Lin Weiwei Tao Yakang Xu Wenjing Niu

Aiming at the problems of microseismic signals from rock mass fracture in deep-buried tunnels with low signal-to-noise ratio (SNR) suffering from coupled interference of multi-source noise, and traditional filtering methods having fixed parameters and poor processing effects on spectral aliasing, this study proposes a ternary coupled adaptive filtering method integrating the Sparrow Search Algorithm, Variational Mode Decomposition and Wavelet Threshold Denoising (SSA-VMD-DWT). First, the noise intrusion characteristics of low-SNR microseismic signals in deep-buried tunnels were analyzed, and the filtering difficulties of white noise, low-frequency noise, high-frequency noise and non-stationary noise were clarified. Subsequently, a parameter optimization framework with the Sparrow Search Algorithm (SSA) as the core was constructed to optimize the key parameters, including the penalty factor α and modal number K of Variational Mode Decomposition (VMD), as well as the wavelet basis and decomposition layers of Wavelet Threshold Denoising (DWT), respectively. A dual-index threshold decision function based on kurtosis and correlation coefficient, and a wavelet packet entropy weighted reconstruction algorithm were designed to realize the collaborative adaptive adjustment of decomposition depth and threshold rules. Finally, the performance of the algorithm was verified through simulation signal experiments and an engineering case of a deep-buried tunnel in Southwest China. The results show that for the simulated signal with a low SNR of 2 dB, the SNR is increased to 12.43 dB, and the root mean square error is reduced to 2.36 × 10−7 after denoising by this algorithm, which is significantly superior to the Empirical Mode Decomposition (EMD) and traditional DWT methods. In the engineering case, the information entropy of the filtered signal is the lowest among all methods, which can effectively suppress multi-band noise and retain the core characteristics of microseismic signals from rock mass fracture, solving the problems of spectral aliasing, detail loss and empirical parameter setting of traditional methods. This method provides a new technical paradigm for the processing of low-quality microseismic signals in deep tunnel engineering and can improve the accuracy of monitoring and early warning for rock mass dynamic disasters.

Geosciences doi: 10.3390/geosciences16040142

Authors: Xianxiang Wang Shanmei Li Zefan Hu Qing Sun

Marine electric-source time domain electromagnetic (TDEM) surveys typically involve the simultaneous movement of transmitters and receivers, which generates a large number of transmitter–receiver pairs. This acquisition geometry creates notable challenges for 3D inversion, mainly because of the large data volume and high computational cost. However, the electromagnetic “sensitive region” for each transmitter–receiver pair is much smaller than the full survey area. Based on this feature, we propose an efficient 3D inversion approach using the footprint technique. By clearly defining the sensitivity region, referred to as the footprint domain, for each pair, the method builds the sensitivity matrix only within localized subsurface regions that significantly affect the observed response. This approach greatly reduces both forward modeling cost and memory requirements. The forward modeling adopts an integral equation method combined with cosine transforms for fast 3D field computation, while the inversion framework uses a regularized conjugate-gradient algorithm, further accelerated by parallel computing under footprint domain constraints. Numerical simulations also examine the effects of offset, time channel, seawater thickness, and resistivity on the footprint domain, helping clarify the spatiotemporal diffusion behavior of TDEM fields in shallow marine environments. Tests on representative models show that the proposed method remains stable and accurate under complex geological conditions while significantly improving computational efficiency. In particular, the footprint domain technique improves inversion speed by about 55% compared with full domain inversion. These results indicate that the proposed approach provides a reliable and scalable option for large-scale 3D inversion of marine TDEM data.

Geosciences doi: 10.3390/geosciences16040141

Authors: Agostino Meo Bruno Massa Sabatino Ciarcia Maria Rosaria Senatore

The Gulf of Taranto (Ionian Sea) is a key transitional sector between the Southern Apennines collisional belt and the Calabrian Arc system, where the expression of Pleistocene–Holocene deformation in the shallow stratigraphic record remains debated. This study focuses on the Taranto Canyon area, the main morphologic feature of the northeastern Gulf of Taranto slope. We integrate high-resolution multibeam bathymetry (10 m grid) with Sparker seismic profiles to (i) define the shallow seismo-stratigraphic framework and (ii) document spatial relationships between shallow discontinuities, morphostructural lineaments, and submarine channel network organization. A simplified tie to the Livia 001 well constrains the subdivision of the shallow succession into four seismic units: the late Pleistocene–Holocene unit (PtH), the Santerno Formation (SNT), the Calcarenite di Gravina (GRA), and the Cupello Limestones (CPL). The PtH interval shows the strongest lateral variability and includes widespread acoustically disturbed bodies and recurrent sub-vertical fluid escape acoustic anomalies. Steep discontinuities producing reflector terminations, minor vertical separation, and localized bending affect PtH and, locally, SNT, with normal fault geometries prevailing where resolvable. Bathymetric mapping reveals multiple lineament families and preferred channel orientations that persist across higher Strahler orders, supporting a structurally conditioned template that guides seafloor morphology, sediment routing, and canyon–slope evolution in the northeastern Gulf of Taranto.

Geosciences doi: 10.3390/geosciences16040140

Authors: Nikolay Bonev

The Circum-Rhodope Belt fringes the Rhodope and Serbo-Macedonian zones in the Alpine orogen of the northern Aegean region. This belt contains Late Paleozoic and Mesozoic metasedimentary successions that record depositional history along the continental margin of Eurasia. Critical successions of the eastern Circum-Rhodope Belt, such as those exposed in the Fanari and Petrota areas, are studied here, integrating their structure, whole-rock geochemistry and U-Pb LA-ICP-MS zircon geochronological context. The Fanari turbiditic succession contains quartz arenite, while the Petrota succession consists of Fe-rich shale and sandstone, and both successions are distinguished by REE-depleted and REE-enriched characteristics and acidic and intermediate arc-related sedimentary sources, respectively. Detrital U-Pb zircon geochronology reveals a Late Carboniferous–Early Permian maximum depositional age of 301.2 ± 8.4 Ma for Fanari quartz arenite and a Late Jurassic maximum depositional age of 147.0 ± 2.0 Ma for Petrota Fe-shale. The results are interpreted in terms of Late Paleozoic continental slope deposition of the Fanari succession along the Eurasian margin and trench-arc sedimentation of the Petrota succession linked to the development of a Jurassic island arc system pertinent to the eastern Circum-Rhodope Belt. These tectonic settings and depositional environments can be used to restore an overall picture of a Late Paleozoic to Mid-Mesozoic sedimentation at the Rhodope–Serbo-Macedonian continental margin of Eurasia. Structures that developed in greenschist facies conditions and N-directed kinematics of the studied successions unequivocally relate them to other units of the eastern Circum-Rhodope Belt and its Late Jurassic tectonic evolution.

Geosciences doi: 10.3390/geosciences16040139

Authors: Nikolaos Avrantinis Panagiotis Koukakis Pavlos Avramidis

The growing global demand for critical raw materials (CRMs) essential to renewable energy, electromobility, and digital technologies has accelerated the need for advanced exploration methods capable of operating in increasingly challenging geological environments. Traditional drilling systems, designed primarily for shallow mineral and hydrocarbon exploration, face limitations in heterogeneous and consolidated formations where rock heterogeneity, variable mechanical strength, and borehole instability restrict operational efficiency. This review bridges geological science and robotic engineering by analyzing the evolution of next-generation autonomous drilling technologies integrating sensor systems, artificial intelligence (AI), and real-time geotechnical feedback. The current work explores how robotic drilling systems can autonomously adapt to variable lithologies, optimize penetration rates, and ensure borehole stability through intelligent sensing and control. The paper reviews the geological, geomechanical and ore deposit characteristics of CRMs, discusses state-of-the-art drilling optimization strategies, and highlights advances in measurement while drilling (MWD), logging while drilling (LWD), and geochemical analysis techniques. It also suggests a list of sensor techniques for possible future integration in autonomous subsurface robotic systems. It concludes by emphasizing the need for integration between subsurface geological modeling and intelligent drilling robotics as a pathway toward sustainable and efficient CRM exploration.

Geosciences doi: 10.3390/geosciences16040138

Authors: Andrei Kholmogorov Nadezhda Syrbu Renat Shakirov Le Duc Anh Le Dinh Nam Elena Maltseva Hitoshi Tomaru Elena Khazanova Anastasia Voitovskaya Irina Isaeva Ngo Bich Huong Tran Hoang Yen Trinh Hoai Thu

The northern Vietnam shelf, particularly the area adjacent to the Red River Fault Zone, is characterized by complex geology and active neotectonics. However, the patterns of degassing and the origins of hydrocarbon gases in this region remain poorly understood. In particular, the potential links between deep-seated fluid migration, fault systems, and gas anomalies in island groundwater systems have not been systematically investigated. This study presents preliminary results of dissolved methane, its homologues (C2–C5), helium, hydrogen, and carbon dioxide measurements in groundwater from Co To Island (Northern Vietnam), with the aim of identifying gas origins and assessing structural controls on fluid migration. A significant methane anomaly was discovered, with concentrations reaching up to 10% by volume in the northwestern part of the island. The hydrocarbon homologous series is traced up to pentane (C5), and CO2 content is also elevated, with a maximum of 5.4%. The average He concentration of 10.8 ppm significantly exceeds atmospheric equilibrium values, with maximum recorded concentrations of 18 ppm for He and 34.5 ppm for H2. Stable carbon isotope analysis of methane (δ13C-CH4 values ranging from −50.2‰ to −49.7‰ VPDB), combined with the presence of a complete C1–C5 hydrocarbon series and elevated mantle/crustal tracers (He, H2), indicates a predominantly thermogenic/metamorphogenic origin for the gases, ruling out a purely biogenic source. The spatial distribution of anomalies is structurally controlled, closely associated with the NE-SW trending Co To Fault system and its intersections with subsidiary faults, as corroborated by recent electrical resistivity tomography data. These findings indicate intensive, focused gas leakage from a deep-seated source, likely related to thermogenic/metamorphic processes and active fault-mediated degassing. The results highlight the significant hydrocarbon potential of the region and underscore the critical role of neotectonic activity in controlling fluid migration pathways in island aquifer systems.

Geosciences doi: 10.3390/geosciences16040137

Authors: Massimo Calcara

Recent years have witnessed growing interest in CO2 and in the possibility of injecting it into the Earth’s crust for multiple purposes. In addition to the fact that pure CO2 is already present in some geological formations, the most debated is Carbon Capture and Storage (CCS), which aims to capture and trap CO2 through water-assisted reactions that promote its precipitation; moreover, proposed technological improvements to geothermal plants foresee the use of pure CO2 as a working fluid and energy carrier for electricity generation in terms of MWh. These applications require detailed knowledge and a deep understanding of CO2 behaviour under non-standard conditions. Upon entering the Earth’s crust, CO2 is subjected to progressively increasing temperature and pressure. The resulting effects are not limited to a reduction in intermolecular distance; they also include changes in molecular geometry, as well as in chemical and thermodynamic behaviour. For instance, a dipole moment may arise even in the gaseous phase as intermolecular distances decrease. Moreover, CO2 typically reaches supercritical conditions at depths of approximately 700 m. It is therefore necessary to account for both phase transitions and variations in molecular structure, as these can significantly influence the surrounding environment and the stoichiometric relationships with other substances. In this work, a steady-state column was simulated, representing CO2 injection down to a depth of 5 km, assuming an average geothermal gradient of 30 °C/km and nine different initial pressures, so nine different steady state columns. The results highlight the presence of a wedge-shaped region acting as a barrier for stepwise-equilibrated CO2: the computed CO2 column profiles avoid this region. This wedge includes part of the liquid–gas boundary under subcritical conditions, as well as the Widom lines above the critical point. It effectively separates two supercritical regimes, namely gas-like and liquid-like domains. In this context, the present work provides insights into the Widom region—possibly extending into subcritical conditions—and into these two distinct regimes. This may have implications for the solvent capacity of CO2 for ionic species. Ultimately, the initial pressure appears to determine the behaviour of CO2 at depth.

Geosciences doi: 10.3390/geosciences16040136

Authors: Hongyu Xu Xi Zhang Zhou Xie Chong Sun Pingzhou Shi Ruidong Liu Lubiao Gao Jinyu Luo Tenghui Lu

Oil and gas exploration conducted in the main fault zone of the Fuman Oilfield has yielded large-scale and high-production results. Against this background, the non-fault zone has emerged as a new domain for oil exploration endeavors. Nevertheless, the establishment of a unified sequence division scheme for the study area remains unachieved, primarily constrained by two key factors: first, the high costs associated with ultra-deep high-density coring operations; and second, the inconspicuous response characteristics exhibited by logging curves. This absence of a standardized scheme has further impeded the progress of oil and gas exploration in the non-main fault inter-region within the study area. Consequently, the present study is based on multi-source data, including seismic data, logging data, and field outcrop data. Magnetic susceptibility measurements from the cement plant section and natural gamma-ray logging data from the Yangjikan section were systematically analyzed to establish cyclostratigraphic frameworks. A sedimentary noise model (SNM) was employed to reconstruct Holocene sea-level fluctuations, enabling precise sequence stratigraphic subdivision within the Fuman Area. Results demonstrate that the Middle-Lower Ordovician Yijianfang–Penglaiba Formations retain robust astronomical cyclicity, validated by high-fidelity orbital forcing signals. Notably, the DYNOT (Dynamic Noise After Orbital Tuning) model effectively decouples orbital-driven sea-level oscillations from local depositional noise, offering a novel approach for sequence boundary identification. This methodology reveals a hierarchical sequence architecture comprising four third-order sequences and 11 fourth-order sequences within the Yijianfang–Penglaiba Formations. Such a framework provides critical insights into facies distribution patterns and non-fault-controlled exploration potential in the Fuman Basin.

Geosciences doi: 10.3390/geosciences16040135

Authors: Vladimir M. Cvetković Dalibor Milenković Tin Lukić

Disaster resilience has become a key focus of risk reduction efforts, but measuring it remains complex due to differences in hazards, development paths, and data systems. This study modifies the Baseline Resilience Indicators for Communities (BRIC) approach, based on the Disaster Resilience of Place (DROP) framework, to evaluate community resilience in Serbia and highlight regional differences. An initial list of 186 indicators was created from international BRIC studies and resilience research, then tailored to Serbian conditions through contextual review and data checks. Indicators were normalized using min–max scaling (0–1), and indicators with negative orientation were inverted to ensure that higher values indicate greater resilience. Scores for each dimension were calculated as equally weighted averages across six areas: social, economic, social capital, institutional, infrastructural, and environmental. The overall BRIC index was derived as the average of these dimension scores. Z-scores facilitated the classification of resilience levels and the comparison between regions. The results show clear regional disparities: in the complete model, Belgrade has the highest resilience (BRIC = 0.557), while Southern and Eastern Serbia have the lowest (BRIC = 0.414). Patterns across dimensions show that Belgrade excels in social and economic capacity but lags in environmental indicators; Vojvodina has the strongest institutional and infrastructural capacity; and Šumadija and Western Serbia perform best in environmental indicators. Correlation analysis revealed multicollinearity, leading to the removal of 14 redundant indicators and the refinement to a set of 57. After this reduction, regional rankings change, with Vojvodina (BRIC = 0.530) and Šumadija and Western Serbia (BRIC = 0.522) emerging as higher-resilience regions, while Southern and Eastern Serbia remain the least resilient (BRIC = 0.456). The adapted BRIC-DROP model offers a clear, locally relevant tool for mapping resilience and guiding targeted policies in Serbia, enabling region-specific efforts to address structural resilience gaps.

Geosciences doi: 10.3390/geosciences16040134

Authors: José Antonio Mantovani Rayonil Carneiro Camilla Kassar Borges Sergio Ibarra-Espinosa José Antonio Aravéquia Gilberto Fisch Dirceu Luis Herdies

This study evaluates the performance of eleven Planetary Boundary Layer (PBL) schemes within the Weather Research and Forecasting (WRF) model over the Central Amazon Basin, focusing on contrasting wet and dry season conditions observed during the GoAmazon2014/5 campaign. High-resolution (1 km) simulations were conducted for representative periods in each season and validated against in situ observations. Model performance was assessed using multiple statistical metrics with the explicit separation of daytime convective and nighttime stable PBL regimes. Results reveal substantial variability among PBL schemes, strongly modulated by the season and diurnal cycle. Overall performance was higher during the wet period, whereas dry period simulations exhibited larger uncertainties, particularly under nocturnal conditions. The Shin–Hong (SH) PBL scheme had the best skill on average to reproduce the observed PBL height (PBLH) during the wet period, while the University of Washington (UW) PBL scheme was the best during the dry period. The Mellor–Yamada–Janjic (MYJ) PBL scheme had the best skill for daytime PBLH in both periods. Spatial analysis demonstrated how PBL schemes impact the PBLH distribution over the Central Amazon Basin, revealing a river-influenced pattern. These findings highlight the strong sensitivity of the Amazon PBL depth to PBL schemes and underscore the importance of appropriate PBL parameterizations and the vertical resolution for tropical applications.

Geosciences doi: 10.3390/geosciences16030133

Authors: Ivan A. Babenko Nailya G. Rizvanova Sergey G. Skublov Yuri A. Bishaev Irina V. Talovina Olga L. Galankina Alexander V. Kuznetsov

Pegmatites with miarolitic cavities have not previously been reported from the Larsemann Hills, East Antarctica, and their age and origin remain poorly constrained. We report the first geochemical and geochronological data for fluorapatite from a newly discovered pegmatite with miarolitic cavities in the Larsemann Hills. Large Fe-rich fluorapatite crystals (up to 5 cm) contain abundant oriented monazite-(Ce) inclusions and display elevated REE (1397–7966 ppm), relatively high Y (945–4192 ppm), and low Sr (52.2–83.5 ppm). Their trace-element signatures plot within the fields of partial melts, high-grade metamorphic rocks, and evolved fluid-rich magmatic systems. U–Pb dating of fluorapatite yields concordant ages of 519 ± 4 Ma (ID-TIMS) and 521 ± 31 Ma (LA-ICP-MS), indicating crystallization during the D4 stage of the Pan-African orogeny. The isotopic equilibrium between apatite and monazite inclusions suggests synchronous formation and late-stage fluid overprinting. Combined geological, geochemical, and isotopic evidence shows that the pegmatite formed in situ as a product of anatexis of the Broknes paragneisses and evolved within a volatile-rich magmatic–hydrothermal system. These results provide the first direct age constraints on pegmatites with miarolitic cavities in Antarctica and shed new light on the final stages of East Gondwana assembly.

Geosciences doi: 10.3390/geosciences16030132

Authors: Shipeng Hu Tiantao Li Weiling Ran Jian Guo Shihua Chen Jing Yuan Hao Jing

The ice–rock interface shear mechanism is fundamental to understanding ice–rock avalanche hazards. This study conducts a series of direct shear tests under various normal stresses to analyze the mechanical response and acoustic emission (AE) evolution of the interface, establishing a shear strength prediction model. Results indicate that the roughness significantly affects mechanical properties and AE responses: as the roughness increases, the shear strength, cohesion, and internal friction angle improve significantly, while peak AE ringing counts and energy exhibit an increasing trend. During failure, the proportion of shear cracks decreases while tensile cracks increase, reflecting a shift in crack development modes driven by the roughness. Based on AE characteristics and stress–displacement relations, the shear failure process is categorized into five stages: initial, crack development, crack propagation, crack coalescence, and residual stages. Incorporating the effects of the roughness and cementation force, a shear mechanical model was established. Experimental data verify the model’s rationality; however, its applicability may be limited when the roughness is excessively high.

Geosciences doi: 10.3390/geosciences16030131

Authors: Jihane Ounar Hicham El Asmi Mohamed Achraf Mediany Rachid Oukhro Kamal Mghazli James Pierce David A. D. Evans Malika Fadil El Hassane Chellai Moulay Ahmed Boumehdi Nasrrddine Youbi Timothy W. Lyons Andrey Bekker

This study provides sedimentological and stratigraphic insights into the Ediacaran fluviolacustrine successions of the Amane-n’Tourhart and Tifernine basins. The Amane-n’Tourhart Basin developed in a post-caldera volcanic setting along the margin of the Oued Dar’a Caldera, whereas the Tifernine Basin formed in a pre-caldera tectono-volcanic context associated with caldera development. The successions provide valuable information about the sedimentary processes operating in late Ediacaran continental environments. Field observations, facies analysis, and petrography reveal a variety of siliciclastic, carbonate, mixed siliciclastic–carbonate, and volcaniclastic facies. These facies form associations indicative of alluvial fan, floodplain, and shallow-water lacustrine settings. Alluvial fan deposits are dominated by conglomerates and sandstones forming braided systems. Fluviolacustrine successions show a transition from clay-rich siltstones with calcareous nodules to nodular and massive limestones, marking a gradual shift from fluvial to lacustrine conditions. Laminated limestones and stromatolites indicate intermittent microbial activity that contributed to carbonate precipitation. Sedimentation was strongly influenced by volcanic inputs and climatic fluctuations, alternating between humid and arid conditions. These factors drove cycles of channel incision, sediment infill, and lake expansion–contraction, illustrating the dynamic interplay of volcanism and climate that modulated deposition in these Ediacaran continental basins, with broad relevance to our understanding of this critical window in the Earth’s history.

Geosciences doi: 10.3390/geosciences16030130

Authors: Marzhan Rakhymberdina Roman Shults Baitak Apshikur Yerkebulan Bekishev Yevgeniy Grokhotov Azamat Kapasov Damir Mukyshev

Rare-metal pegmatite–greisen systems are commonly small, structurally controlled, and difficult to delineate using conventional mapping alone. This study proposes a multiscale remote-sensing workflow for prospecting Li–Nb–Ta–Cs mineralisation in the Kalba–Narym rare-metal belt (East Kazakhstan) by integrating Sentinel-2 multispectral imagery, UAV-derived centimeter-scale orthomosaics, structural (lineament) analysis, and field-based mineralogical–geochemical validation. Sentinel-2 responses were first calibrated using known occurrences to derive alteration proxies related to greisenisation, silicification, Na-metasomatism, and oxidation. These proxies were combined into an Integrated Hydrothermal Alteration Index (IHAI) to highlight areas where multiple alteration processes overlap. Lineament mapping from Sentinel-2 and DEM products indicates dominant NW–SE and NE–SW structural trends, zones of elevated lineament density and intersection systematically coincide with high IHAI values. UAV orthomosaics refine satellite-scale anomalies by resolving quartz-vein networks, fracture corridors, and surface-alteration textures that are not detectable at 10–20 m resolution. Mineralogical and geochemical data confirm that high-IHAI targets correspond to albitised pegmatites and greisenised rocks enriched in Li, Nb, Ta, and Cs. The results demonstrate that combining freely available Sentinel-2 data with UAV observations and targeted ground validation provides a cost-effective and transferable framework for reducing false positives and prioritising exploration targets in structurally complex granitoid terranes.

Geosciences doi: 10.3390/geosciences16030129

Authors: Sanjoy Kumar Pal Kousik Nanda Soumen Sarkar Stelios M. Potirakis Masashi Hayakawa Sudipta Sasmal

Global Positioning System (GPS)-derived ionospheric electron concentration measurements provide a powerful observational framework for seismo-electromagnetic studies, enabling quantitative investigation of lithosphere–atmosphere–ionosphere coupling processes through statistically detectable perturbations in ionospheric electron concentration. We analyze GPS-derived Vertical Total Electron Content (VTEC) variations associated with the 14 August 2021 Haiti earthquake (Mw 7.2) and the 11 January 2022 Cyprus earthquake (Mw 6.6) using data from nearby International GNSS (Global Navigation Satellite System) Service (IGS) stations located within their respective earthquake preparation zones. VTEC time series spanning 45 days before and 7 days after each event are processed to remove the diurnal component, yielding residuals that isolate short-term ionospheric variability. Anomaly detection is performed using three statistical frameworks: a Gaussian mean, standard deviation model, a robust median/median absolute deviation (MAD) model, and a distribution-free quantile-based model. Daily “occurrence” and “energy” indices are constructed to quantify the frequency and cumulative strength of detected anomalies, respectively. While the indices exhibit similar temporal patterns across all methods, they indicate frequent anomaly detection, limiting statistical selectivity. To address this, both indices are normalized by their median values and filtered using a 95% quantile threshold, retaining only extreme deviations. This procedure substantially reduces background fluctuations and isolates a small number of statistically significant anomaly peaks. For both earthquakes, enhanced anomaly activity is identified in the weeks preceding the events, whereas post-event peaks coincide with periods of elevated meteorological and geomagnetic activity. The results demonstrate that normalization combined with robust statistical methods is essential for discriminating significant ionospheric TEC anomalies from background variability.

Geosciences doi: 10.3390/geosciences16030128

Authors: Zheng Su Yifan Wu Chao Yang Nengyou Wu

Fluid seepages and seabed pockmarks are widely observed on continental margins worldwide in hydrate- and non-hydrate-bearing sediment. Subsurface gas chimneys connecting seafloor pockmarks to underlying gas reservoirs are commonly revealed by seismic reflection data, indicating pathways of past and present fluid migration. Fluid seepage occurs when the seal of a gas reservoir is breached, allowing fluids to migrate upward and vent at the seafloor, forming pockmarks. In hydrate-bearing settings, gas reservoirs beneath hydrate layers typically consist of coexisting water and gas phases. However, quantitative constraints on gas saturation in free-gas zones beneath hydrates inferred from pockmark morphology remain limited. In this study, a two-phase pockmark model was developed to investigate gas-chimney growth and pockmark formation, and to estimate gas saturation in free-gas zones below hydrates using pockmark depth and gas-zone thickness as key parameters. The model was applied to the Storegga Slide region off Norway, where hydrates, pockmarks, and chimney-like seismic anomalies have been documented. Here, the application is intended to represent localized near-threshold (pre-seepage) conditions leading to pockmark initiation, rather than the present-day post-venting state. Model results for the initiation (near-threshold, pre-venting) stage indicate that the effective gas saturation in the free-gas reservoir beneath the hydrates was approximately 1.36–1.58% for gas-zone thicknesses of 50–100 m, and that the corresponding chimney-propagation timescale during initiation was on the order of ~200 years. These estimates represent threshold conditions required for seal breach and pockmark formation rather than present-day seepage states. During venting, methane gas may form hydrates within the chimney inside the hydrate stability zone, while authigenic carbonates precipitate in pockmarks and shallow sediments. These secondary hydrates and carbonates eventually seal the chimney, leaving behind a residual gas chimney in the subsurface sediment.

Geosciences doi: 10.3390/geosciences16030127

Authors: Miriani Makadze George E. Mustoe

The widespread abundance of silicified wood and fossil leaves in southwestern Georgia is associated with the upper Miocene-lower Pliocene volcanic deposits of the Goderdzi Formation. Neogene volcanic terrains frequently preserve exceptionally detailed fossil records, providing valuable insights into ancient environments, climate regimes, and vegetational dynamics. Extensive upper Miocene volcanic activity produced thick pyroclastic deposits, lahar flows, and localized sedimentary basins that facilitated the rapid burial and preservation of diverse plant remains, including silicified wood and well-preserved fossil leaves. The mineralogy of Goderdzi Formation fossil woods is surprisingly complex, with compositions that include opal-A, opal-Ct, chalcedony, and microcrystalline quartz. These minerals are evidence of variations in hydrothermal fluid circulation that led to episodes of mineral precipitation that typically occurred in several discrete steps.

Geosciences doi: 10.3390/geosciences16030126

Authors: Iva Kolenković Močilac Marko Cvetković Zrinka Stojanović Anđela Papić

Reliable subsurface temperature estimates are crucial for most geoenergy projects, as they directly influence the properties of both rocks and fluids. They are particularly important in geothermal energy exploration, where errors in estimating the static formation temperature (SFT) can lead to significant misinterpretations, potentially resulting in incorrect classification of the geothermal resource. Various corrections are applied to bottom-hole temperatures (BHTs), with the Horner correction being the most widely used. In addition, empirical methods have been developed to improve accuracy at the local scale. In this study, maximum temperature values (Tmax) reported for deep exploration wells in the Sava and Drava Basins were compared to both Horner-corrected temperatures (HPCTs) and those recorded during drill-stem tests (TDST). In both basins, Tmax values frequently significantly diverge from HPCT measurements, emphasizing the limited reliability of Tmax for estimating subsurface temperatures. In the Sava Basin, 61% of wells show Tmax-HPCT differences greater than 10 °C, and in seven wells the discrepancy exceeds 20 °C. Similarly, in the Drava Basin, nearly half of the wells exhibit differences greater than 10 °C, with five wells showing deviations above 20 °C. In most cases, the reported Tmax values do not represent true maxima, so the linear regression was performed between Tmax and temperatures obtained from DST measurements, providing a basis for refining subsurface temperature estimates.

Geosciences doi: 10.3390/geosciences16030125

Authors: Jeff B. Langman Amanda Balogh D. Eric Aston Timothy E. Link Emile Milan Bridget Eckhardt Sarah Mulzet

Mining at the Red Dog Mine generated a 60 million-tonne waste rock stockpile that produces acid rock drainage with pH values typically below 3. The drainage chemistry is controlled by the competing kinetics of acid-generating iron sulfide weathering and acid-neutralizing carbonate and phosphate dissolution. To evaluate the interaction of these reactions, waste rock was collected from the stockpile by drilling a borehole from the surface to a depth of 52 m, terminating at the shale bedrock. A temporal paste pH test was conducted to extend the utility of the static paste pH test to a continuous (30 min) measurement of pH and ORP over a 24-h period. The 24-h paste pH results revealed multiple acid-generating and acid-neutralizing reactions: pH values ranged from 3.31 to 6.96. Mineralogical analysis indicated initial acidic conditions in 12 of the depth intervals (upper and lower zones) were due to the release of stored acidity from soluble iron sulfate minerals. Subsequent pH increases were driven by calcite dissolution and likely phosphate and clay mineral acid-neutralizing reactions. Conversely, late-stage pH decreases in the lower middle zone indicated the presence of highly reactive/available iron sulfide surfaces, which allowed for earlier acid generation compared to less reactive/available iron sulfide minerals in other zones. The utility of this temporal paste pH test and associated mineral analysis is to understand the mineralogical controls on early temporal acid generation to guide batch reactor testing of remaining acid potential under saturated conditions. This sequential approach provides critical information for predicting long-term acid generation and information management of the stockpile for mine site remediation and closure.

Geosciences doi: 10.3390/geosciences16030124

Authors: Angela Baldanza Maurizio Triscari Marcella Di Bella Giuseppe Sabatino

The identification of calcareous foraminifera and nannofossils in archaeological ceramics (tiles and bricks from the Archaic to Roman ages) of Naxos and Taormina (Sicily) has, along with other evidence and archaeometric analyses, addressed aspects of technology and raw material source areas. Microfossils, like the other aplastic inclusions, help to interpret ceramic pastes. This paper provides, for northeastern Sicily, a contribution demonstrating the importance of an integrated approach in the study of archaeological ceramics; micropaleontological analysis supports mineralogical, petrographic and chemical data to constrain interpretations of provenance and technology. The preservation of foraminifera calcitic tests and coccoliths is an additional key to identifying errors, failures and strategies during the ancient ceramic firing process. Comparisons with the micropaleontological content of locally outcropping clay deposits have allowed for the unambiguous identification of the clay sources used for ancient ceramic production in the region.

Geosciences doi: 10.3390/geosciences16030122

Authors: Mustafa A. Elsagheer Hilmy E. Moussa Ayman E. Maurice Paul D. Asimow Oliver D. Wilner Maysa M. N. Taha Adel A. Surour Mokhles K. Azer

We report, for the first time, waimirite-(Y) in Egypt. This is only the third reported occurrence of this mineral in the world. This observation arose during our study of the rare earth element (REE) mineralization associated with the Neoproterozoic rare-metal granite intrusion in Wadi Abu Rusheid in the Eastern Desert of Egypt. The principal lanthanide and yttrium (Y) hosts in the area are waimirite-(Y) and bastnäsite-(Ce) in leucogranite and bastnäsite-(Y) in adjacent metasedimentary country rock. The leucogranite is a strongly fractionated, metaluminous to weakly peraluminous (A/CNK = 0.98–1.03), medium- to high-K calk-alkaline I-type granite. The metasediments are composed of upper greenschist to lower amphibolite-grade biotite schists with variable amounts of amphibole, graphite, and garnet. Leucogranite contains accessory Li-bearing mica, garnet, zircon, fluorite, and columbite in addition to the REE minerals. It is enriched by three orders of magnitude relative to primitive mantle in Li, Rb, Th, Ta, Nb, Pb, U, and Sn; relative to these highly enriched elements the concentrations of Sr, Ba, Ga, Zr, Hf, and Y are notably low. The REE patterns of most samples show strong enrichment in heavy relative to light REE but occasional samples have light REE-enriched patterns controlled by accessory REE minerals, and all display strong negative Eu anomalies (Eu/Eu* ≤ 0.05). The whole-rock chemistry of the metasedimentary units are different; relative to average upper continental crust they show enrichments of one to two orders of magnitude in Li, Rb, Pb, Sn, Cs, and sometimes Cr and Zn. The REE patterns of the metasedimentary units are nearly flat, with some samples showing negative Eu anomalies. Waimirite-(Y), nominally YF3, also contains several weight percent each of Yb, Dy, and Er. The empirical formula (based on one cation) is (Y0.55Ce0.02Pr0.01Nd0.02Sm0.02Gd0.02Dy0.05Er0.04Yb0.05Th0.05Ca0.16Pb0.01)∑1.00(F2.48O0.52)∑3.00. Bastnäsite-(Ce) in leucogranite samples, nominally Ce(CO3)F, also has several weight percent each of Nd2O3 and La2O3. The REE host in metasedimentary rocks is bastnäsite-(Y), nominally Y(CO3)F, but also rich in Nd2O3 (11–19 wt.%) and La2O3 (4–14 wt.%). It is intimately associated with fluorophlogopite. The geochemical, mineralogical, and textural evidence indicates that waimirite-(Y) and bastnäsite-(Ce) in leucogranite crystallized from granite-derived F- and CO2-bearing hydrothermal fluids, whereas the source of Y for growth of the bastnäsite-(Y) in the metasedimentary rocks is unclear; the large negative Ce anomaly in bastnäsite-(Y) suggests an oxidizing supergene setting. Despite their proximity, if there is a genetic connection between the mineralization in the granite and in its country rocks, the relationship is not evident from elemental patterns or host mineralogy.

Geosciences doi: 10.3390/geosciences16030123

Authors: Yangyang Zhao Hesheng Hou Dongzhao An Wei Fu Jiaodong Zhang Youfeng Gao Feng Ma

The Xujiaweizi Fault Depression in the Songliao Basin is a significant area for deep natural gas exploration, and the Shahezi Formation has been recognized as the primary hydrocarbon-source rock. This research integrates core, logging, and seismic data from Well SK2, the world’s first scientific drilling well to reach a depth of 7018 m and obtain 2624 m of continuous cores from the Shahezi Formation. The study aims to redefine the stratigraphic framework, resource characteristics, and sedimentary evolution of the formation in the Cretaceous period. The Shahezi Formation, dating from 118 to 112 Ma (mid-Aptian to early Albian), is divided into five third-order sequences (SQ1–SQ5). The upper section of SQ5 and SQ2 shows the highest potential for deep gas, featuring high-maturity Type III kerogen, 35 gas anomaly layers with a total thickness of 79 m, and a 59% proportion of dark mudstone. A three-stage sedimentary evolution model, including initial faulting, intense faulting, and contraction, is proposed, establishing a link between terrestrial sedimentation and global Early Cretaceous events (e.g., OAE1b). This research provides crucial insights for deep gas exploration and global marine–terrestrial sedimentary comparisons.

Geosciences doi: 10.3390/geosciences16030121

Authors: Yanliu Ding Xixi Liu Jing Tian Shiyong Yan Lixin Lin Han Ma

The Bayan Obo Mining District, recognized as the largest rare-earth resource base worldwide, has experienced significant surface instability due to intensive mining and large-scale dumping activities. To address the challenges posed by complex geological conditions and mining-induced disturbances, this study employs dual-ascending Sentinel-1A C-band Synthetic Aperture Radar (SAR) datasets (Path 11 and Path 113) and applies the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique to retrieve time-series deformation along the line-of-sight (LOS) direction for each track. Through temporal normalization and spatial matching, paired LOS observations from the two tracks were established. Based on the SAR observation geometry and under the assumption that the north–south component is negligible, a LOS projection model was constructed and a geometric decomposition was performed to derive the east–west and vertical two-dimensional deformation fields. The results indicate that the study area is generally stable, while significant subsidence occurs in the northern pit and adjacent waste-dump zones, with local maximum rates approaching 50 mm/year, predominantly controlled by the vertical component. The two-dimensional deformation analysis reveals that vertical displacement dominates surface motion, whereas east–west movement shows smaller amplitudes but clear directional concentration. In particular, the east–west slopes exhibit slightly higher velocities, suggesting a lateral adjustment tendency along this direction, likely related to the overall east–west geometric configuration of the open-pit and waste-dump areas. Time-series observations further reveal that precipitation-related surface deformation occurs with an approximate two-month delay, reflecting the hydrological–mechanical coupling processes of rainfall infiltration, pore-water pressure propagation, and dump-material consolidation. Overall, this study reveals the multi-dimensional deformation characteristics and precipitation-driven stage-wise response of the mining area, demonstrating the effectiveness of the dual-ascending SBAS-InSAR for two-dimensional deformation monitoring in highly disturbed environments, and providing a scientific basis for surface stability assessment and geohazard prevention.

Geosciences doi: 10.3390/geosciences16030120

Authors: Isabelle Moretti Alain Prinzhofer Vincent Roche

This study presents the first comprehensive soil gas survey across southern Uruguay’s H2 prospective terranes. A pre-field trip selection was done on the basement rock nature, as well as vegetation anomalies in subcircular depressions and fault presence. The Neoproterozoic terrane, north of Punta del Este, and the Archean Rio de la Plata Craton, north of Montevideo, as well as along the suture zones between the two, were targeted. Our findings reveal substantial H2 concentrations, significantly outperforming many established basins worldwide. The suture zones act as critical migration conduits for H2 coming from a deeper structural level. Slightly abnormal helium signatures confirm an active, deep-sourced fluid system, particularly within the Sierra Ballena and Cordillera shear zones. The Archean Rio de la Plata Craton appears promising but has only been partially sampled and warrants further investigation. These results underscore the high potential of Uruguay as a new frontier for natural hydrogen exploration.

Geosciences doi: 10.3390/geosciences16030119

Authors: Abdullah Kellevezir Ekrem Tuşat Mustafa Tevfik Özlüdemir

The Earth’s lithosphere, the rigid outermost layer of the planet, is composed of numerous tectonic plates of varying sizes that move over the underlying asthenosphere. The motion and interaction of these plates give rise to a wide range of geodynamic processes. Accurate monitoring of these processes is essential for maintaining a stable, up-to-date, and reliable terrestrial reference frame. This study investigates the horizontal and vertical motions of the Antarctic Plate resulting from its interactions with adjacent plates. Tectonic plate movements can be determined using several space-geodetic techniques, including Global Navigation Satellite Systems (GNSS), Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), and Interferometric Synthetic Aperture Radar (InSAR). Among these methods, GNSS is currently the most widely used, as plate motions can be derived from continuous observations recorded at permanent stations and processed using scientific or commercial software. Within the scope of this research, GNSS data collected between 2020 and 2023 were processed using the GAMIT/GLOBK V.10.7 software package to estimate the coordinates and velocities of stations located on the Antarctic, South American, African, and Australian Plates in the ITRF14 reference frame. Furthermore, plate-fixed solutions were generated to analyze the relative motion of the Antarctic Plate with respect to neighboring plates. The results indicate that the Antarctic Plate moves at an average velocity of approximately 4–18 mm/year in the ITRF14 frame. The plate diverges from both the African and Australian Plates and exhibits predominantly strike-slip motion relative to the South American Plate. A comparison with existing global plate motion models demonstrates that the obtained velocities are consistent within 0–5 mm/year.

Geosciences doi: 10.3390/geosciences16030118

Authors: Fei Li Lin Wang Zhifeng Liang Jinan Wang Chuanqi Zhu Ruiyang Yuan

Traditional methods for geostressfield inversion face issues such as weak physical interpretability and insufficient generalization ability. This study pioneers the application of Physics-Informed Neural Network (PINN) to this problem, developing a data- and physics-driven inversion algorithm. The framework incorporates a constitutive-equation-based regularized loss function as a hard constraint during training to ensure physical consistency. To address boundary load uncertainty, two quantification approaches—Bayesian linear regression and surrogate model optimization—are proposed to establish 95% confidence intervals for boundary coefficients. Verification based on simple three-dimensional models and actual geological models of mines shows that PINN inversion achieves a mean absolute relative error as low as 0.0772%, with an error of 15.67% under sparse sampling conditions—significantly lower than the 31.07% error of the traditional Back propagation neural network. This demonstrates excellent robustness and data efficiency. In the practical engineering application of complex geological bodies, the average error of principal stress inversion is 9.35% with a minimum error of 0.137%. All inversion results fall within the permissible accuracy range of engineering, and the stress distribution conforms to basic laws, with an average error of 0.453 in the constitutive relation. Compared with BP neural network and multiple linear regression methods, it shows obvious accuracy advantages. This method provides a new solution for intelligent ground stress prediction with high accuracy, high efficiency, and strong physical interpretability, and also lays the foundation for early identification of geological disasters.

Geosciences doi: 10.3390/geosciences16030117

Authors: Chenge Zheng Yiwei Wang Xiaowei Huang Weijiao Ma Jinzhong Liu Qiang Wang Cui Weng Yong Li

Unconventional shale resources remain crucial to energy security. In situ conversion technology (ICP) offers a promising pathway for exploiting low–maturity shale, yet the distinct roles of kerogen and bitumen during thermal conversion are not fully understood. This study investigates the decomposition behavior of kerogen and extracted bitumen from the Shahejie Formation through gold–tube pyrolysis experiments at 50 MPa and heating rates of 2 °C/h and 20 °C/h. The results show that the yield curves of C1, C2–C5, and C6–C14 generated from kerogen and bitumen exhibited similar trends. In contrast to the C15+ fraction from kerogen, which initially increased and then decreased, the yield of C15+ from bitumen began to decline from the onset of cracking. Additionally, the CO2 generated from the kerogen continued to increase until the end of pyrolysis, whereas the CO2 from the bitumen reached its maximum at an EasyRo of approximately 1.8%. The kinetic results show that bitumen has a higher activation energy for gas generation than kerogen, while kerogen has a higher activation energy for oil generation than bitumen. A heating program of 1 °C/day rate, 324 d duration, and a final temperature of 360 °C was applied to predict oil and gas generation during ICP. Below 326 °C, the proportion of C1 and C2–C5 contributed by kerogen increased and exceeded 90%. Although kerogen’s contribution ratio of C6–C14 exhibited fluctuating variation characteristics, it remained above 50% across most of the intervals. The gas–to–oil ratio increased rapidly above 299 °C and reached 375 m3/m3 by the end of heating.

Geosciences doi: 10.3390/geosciences16030116

Authors: Luciano Telesca Lev V. Eppelbaum Georgios Balasis

Geophysics represents a dynamic research field that delves into the intricate physical properties and processes that shape the Earth and its surrounding space environment [...]

Geosciences doi: 10.3390/geosciences16030115

Authors: Krzysztof Fuławka Bogumiła Pałac-Walko Lech Stolecki

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Geosciences doi: 10.3390/geosciences16030114

Authors: Mason Jacketta Michael S. Thorne Surya Pachhai Ivan Tochimani-Hernandez Tonie van Dam Christian L. Hardwick Ebenezer Adomako-Mensah William P. Johnson Leif S. Anderson

Water levels in the Great Salt Lake (GSL), UT, USA, have been declining overall since 1989, leading to a 70% decrease in surface area. To understand GSL’s future, we seek to image fresh groundwater input and lithologic variation along the lake’s boundary. Determining the amount of groundwater recharge into GSL is crucial for lake management but currently unknown. During the Fall of 2024 and Spring 2025, we conducted 16 electrical resistivity tomography (ERT) and six transient electromagnetic (TEM) surveys along the southern shore of GSL between Burmester Road (to the West), Saltair, and Lee’s Creek (to the East). These measurements indicate a low-resistivity layer consistent with brine pore-water, with variable thickness ranging from 7.1 ± 0.1 m at Burmester to 9.6 ± 0.2 m at Saltair. The Saltair region shows a high-resistivity layer, consistent with a 4.4 ± 0.05 m thick layer of mirabilite. This layer contains vertical conduits that allow saline pore-water to upwell onto the surface forming evaporite deposits. Near Lee’s Creek, we find evidence of high resistivities consistent with fresher groundwater as shallow as 2.8 ± 0.03 m, where increased permeability along the paleo-Jordan River corridor may provide a path for groundwater recharge from the Wasatch Mountains.

Geosciences doi: 10.3390/geosciences16030113

Authors: Marfasran Hendrizan Mutiara Rachmat Putri Fareza Sasongko Yuwono Rubiyanto Kapid Winda Eka Mandiri Puteri Anisa Ulfatu Hasanah Lia Jurnaliah Praptisih Praptisih Harisma Harisma

The Late Miocene is known as a period of long-term Cenozoic global cooling and decreasing concentrations of atmospheric CO2. The conditions provide the opportunity to assess the Earth’s climate sensitivity in altering internal and external drivers in a warmer world with similarity to the modern continental configuration. However, relative warmer Sea Surface Temperature (SST), a deepened thermocline, and reduced upwelling may have occurred in the tropics during the Late Miocene global cooling. Here, we present foraminiferal biostratigraphy data from the Middle Miocene–Pliocene succession in the Halang Formation in the Banyumas Basin in Indonesia. An increase in the planktonic foraminifera Trilobatus trilobus and Orbulina universa during the Late Miocene in the Indian Ocean indicates relative surface temperature warming and reduced productivity inferred from assemblage shifts. Reduced productivity was caused by decreasing upwelling intensity during the Late Miocene based on Globigerinella obesa assemblages. Reduced upwelling in the south of Java is supported by elevated numbers of surface/mixed-layer species (i.e., Trilobatus sacculifer and Trilobatus immaturus). We suppose the distribution of enhanced upper-layer stratification in the eastern Indian Ocean was not only driven by oceanic forcing but was also transferred intensively into the Indian Ocean by atmospheric forcing of strengthening equatorial trade winds. Changes in the Walker circulation controlled a reduction in upwelling over the eastern tropical Indian Ocean and a deeper thermocline during the cooling climate in the Late Miocene.

Geosciences doi: 10.3390/geosciences16030112

Authors: Yuanfa Ji Zijun Lin Xiyan Sun Jing Wang

This study proposes a hybrid landslide displacement prediction model based on multi-strategy integrated optimization to address high nonlinearity and limited accuracy. An improved SFOA with Lévy flight, dynamic exploration adjustment, and stagnation detection enhances global search and convergence. The optimized SFOA (OSFOA) is employed to optimize CEEMDAN using minimum envelope entropy, reducing hyperparameter subjectivity and decomposing cumulative displacement into multi-scale components. The trend term is predicted by a Bayesian-optimized ARIMA, while periodic and stochastic terms are further decomposed by VMD and predicted using Bayesian-optimized SVR. GRA-MIC is applied to select key influencing factors and optimize model inputs. Results show that the proposed method improves accuracy and stability, reducing RMSE by about 82% and 52% compared with SSA-SVR and the baseline single decomposition model, respectively. The study further identifies monthly rainfall change and two-month reservoir level variation as the dominant driving factors for the displacement evolution, providing an effective and interpretable approach for complex landslide early warning.

Geosciences doi: 10.3390/geosciences16030111

Authors: Yulei Tan Jianyu Huang Liyuan Zhang Laijun Lu Baopeng Chen Tongyuan Liang Lin Pan

Sandstone uranium deposits exhibit stratabound mineralization and strong vertical heterogeneity in geological space, which complicates the identification of uranium anomaly layers and their integration into deposit-scale 3D models using borehole datasets. In this paper, we propose a UAPC Fourier layer identification (UFLI) method for uranium anomaly layer identification. The method is based on multi-log feature construction, random forest-based estimation of a depth continuous uranium anomaly probability curve (UAPC), and improved Fourier vertical variation analysis. We used 19 boreholes arranged on four exploration lines (ZKA-ZKD) of the Daying uranium deposit in the northern Ordos Basin (north central China), for the validation. The proposed UFLI method identified 51 uranium anomaly layers at a 5 m sampling interval, forming discrete vertical clusters within the drilled successions. The results indicate that anomalies are overwhelmingly concentrated in the Middle Jurassic Zhiluo Formation, particularly within the lower Zhiluo member, with an anomaly-bearing depth range of approximately 550–745 m. Comparison with known mineralization records shows that both industrial and ordinary mineralization intervals are captured within the anomaly layers. Then, based on inter-borehole continuity of anomaly layers, we reconstructed five uranium orebodies (orebodies 1–5) and describe their distribution characteristics. The proposed method provides a technical means for subsurface visualization and exploration targeting in sandstone uranium systems.

Geosciences doi: 10.3390/geosciences16030110

Authors: Khemruthai Kheamsiri Naofumi Akata Chutima Kranrod Hirofumi Tazoe Tarika Thumvijit Ilsa Rosianna Haruka Kuwata Krit Khetanun Narit Yimyam Yusuke Unno Akira Takeda

Granitic soils in the Highlands support the cultivation of Arabica coffee in northern Thailand; however, their geochemical and radiological properties are inadequately defined. This study examined major oxides, trace elements, natural radionuclides, and extractable phosphorus in granitic-derived coffee soils from the Agricultural Innovation Research, Integration, Demonstration, and Training Center (AIRID) in Chiang Mai. Twenty soil samples were obtained from 10 locations at two depth intervals (0–30 cm and 30–60 cm). Major and trace elements were analyzed via X-ray fluorescence (XRF), natural radionuclides were analyzed through high-purity germanium (HPGe) gamma spectrometry, and extractable phosphorus was determined using the Bray II method. The soils demonstrate remarkably high 40K activity concentrations (1.2–1.9 kBq kg−1) and increased K2O contents (4.9–7.8 wt%), about three to five times more than worldwide soil averages according to Reimann & de Caritat, indicating enrichment from potassium-rich granitic rocks. Major oxide compositions suggest extensive tropical weathering, characterized by elevated SiO2 (>60 wt%) and Al2O3 (>14 wt%), alongside significant depletion of CaO and MgO (<1 wt%). In topsoil, Bray II–extractable phosphorus constitutes 10–25% of total phosphorus and has a robust positive connection with P2O5 (R2 = 0.95, p < 0.001), signifying surface accumulation and restricted vertical mobility. Multivariate analysis indicates lithogenic grouping of trace elements with negligible vertical redistribution. These findings establish a geochemical and radiological baseline for highland coffee soils in northern Thailand, with implications for soil fertility assessment, soil–plant transfer research, and evaluations of natural radioactive exposure related to coffee production.

Geosciences doi: 10.3390/geosciences16030109

Authors: Filipa Moreno Marina Cabral Pinto Orquídia Neves Rosana Neto

Soil provides essential ecosystem services and is pivotal for achieving multiple United Nations (UN) Sustainable Development Goals amid growing population pressures and resource demands. In arid to semi-arid regions such as Maio Island (Cape Verde), nutrient-poor soils and unsustainable land-use practices increase agricultural vulnerability, while volcanic geochemistry introduces elements that are not human friendly, further challenging environmental quality and long-term sustainability. Assessing soil (physical–chemical–biological) condition is therefore crucial for informed environmental and land-use planning. Here, Maio’s topsoil was evaluated using protocols adapted from Santiago, the largest Cape Verdean island. Estimated Background Values (EBVs) indicated naturally elevated V, Cr, Ni, Co, and Cu concentrations, consistent with mafic volcanic terrains. Robust Principal Component Analysis (rPCA) revealed geochemical groupings linked to volcanic–sedimentary units, with the dominant component (PC1) defined by Co–V–Cu–Mn–Ni versus As–Cd. Environmental Risk Indices (ERIs) and Multi-Element ERIs (ME–ERIs) quantified elemental enrichment relative to international land-use standards (residential and agricultural) and subsequently to Maio’s EBVs. The highest exceedances were observed for Cr, Co, Ni, V, and Cu, whereas As, Cd, Hg, Pb, and Zn fell within thresholds. The EBV-based assessment identified fewer exceedances than stricter international guidelines, though a few multi-element “hotspots” persist, highlighting potential land-use constraints and the need for preventive management. Overall, the integrated EBV/ERI/ME–ERI framework establishes an environmental geochemical baseline for Maio and offers a screening tool applicable across the entire archipelago.

Geosciences doi: 10.3390/geosciences16030108

Authors: Yuangui Zhang Jingbin Cui Maoshan Chen Lei Li Ruidong Han Wentao Wang

Stratigraphic forward modeling (SFM) is a numerical approach used to reconstruct sedimentary basin evolution by simulating the infilling and tectonic evolution process of strata. The challenge is that existing approaches inevitably require trade-offs among modeling fidelity and computational cost. We present a novel clastic stratigraphic forward modeling (CSFM) approach to reducing computational cost while retaining key flow and transport behaviors relevant to stratigraphic architecture. In CSFM, Lagrangian water particles affect momentum and sediment, while a fixed Eulerian grid stores topographic elevation and lithologic fractions. A simplified form of the Navier–Stokes equations is proposed to compute the trajectories of fluid particles, which can greatly reduce the computational cost. Sediment dynamics are represented by coupled suspended load and bedload modules. To validate CSFM, we constructed a synthetic alluvial fan model and performed stratigraphic forward modeling on it. Five lake-level cycles were imposed and results showed that cyclic sand–clay couplets and isolated channel sand bodies were formed during repeated progradation and backstepping. These results are consistent with established sedimentological knowledge, confirming the geological plausibility of CSFM.

Geosciences doi: 10.3390/geosciences16030107

Authors: Ke Wang Jianwu Zhang Yang Liu Ziyu Yuan Weiwei Zhao Chao Liu

The Ordos Basin hosts significant shale gas resources in China, yet its marine-continental transitional sedimentary setting causes intense reservoir heterogeneity that severely hinders accurate sweet spot identification in the Permian Shanxi Formation. This study aims to reveal the synergistic controls of lithofacies, mineralogy, and organic matter on shale gas sweet spot formation in the southern Yishan Slope of the eastern Ordos Basin. A multi-dimensional characterization approach was adopted, integrating drilling/logging data and systematic core analyses including X-ray diffraction (XRD), organic geochemical testing, porosity/permeability measurement, and on-site gas content desorption, to quantify reservoir heterogeneity across lithofacies, mineralogy, organic geochemistry, and petrophysical properties. The results show that three lithofacies associations are identified in the target interval: mud-wrapped sand, sand-mud interbedding, and sand-wrapped mud, among which sand-mud interbedding and mud-wrapped sand associations exhibit higher total organic carbon (TOC) contents and strong inter/intra-well heterogeneity. The organic matter in the reservoir is dominated by Type III kerogen, with TOC values ranging from 0.04% to 12.15%, and the Shan 2 Member shows significantly higher average TOC (2.55%) than the Shan 1 Member (1.36%). The reservoir is characterized by ultra-low porosity (average of 0.77%) and low permeability (average of 0.26 × 10−3 μm2), with mesopores and macropores contributing over 99% of the total pore volume and showing a significant positive correlation with gas content. Quartz (average of 34.86%) and clay minerals present strong vertical heterogeneity, with the Shan 2 Member being more heterogeneous than the Shan 1 Member due to differences in sedimentary environment evolution. A TOC threshold of 1.5% is determined for sweet spot identification in the study area, and shale gas sweet spots are synergistically controlled by high TOC abundance, moderate brittle mineral content, and 0.1–3 m thick sandy interbeds. This study enriches the theoretical understanding of marine-continental transitional shale reservoirs and provides a scientific basis for sweet spot prediction and development optimization in similar heterogeneous shale gas systems worldwide.

Geosciences doi: 10.3390/geosciences16030105

Authors: Yang Su Jie Chen Jiao Wang

This study investigates the rare-earth element (REE) geochemistry of twenty-nine clastic rock samples from the Paleogene Liushagang Formation in the Weixi’nan Sag. The primary objectives were to quantitatively evaluate the depositional paleoenvironment, determine the provenance lithology, and constrain the tectonic setting of the source area. Results reveal distinct chondrite-normalized REE distribution patterns characterized by light REE (LREE) enrichment, relatively flat heavy REE (HREE) segments, and pronounced negative Eu anomalies. The cerium anomaly index (Ceanom, normalized to the North American Shale Composite) ranges from −0.06 to 0.00, implying broadly suboxic to anoxic-reducing conditions in the water column during deposition. The chondrite-normalized (La/Yb)N ratio, utilized as a proxy for relative depositional residence time, decreases stratigraphically from member 3 to member 1, reflecting a transition to shorter residence times and higher relative sedimentation rates. Laterally, (La/Yb)N increases toward the basin center, accurately recording progressively lower sedimentation rates basinward. Provenance analysis indicates that the sediments were predominantly derived from felsic igneous rocks of the upper continental crust. Spatially, the northern steep-slope belt reflects a uniform source, whereas the southern gentle-slope belt and the Weixi’nan low-uplift periphery record multisource mixed inputs. Finally, tectonic discrimination reveals an “active continental margin” affinity. This geochemical signature represents the inherited tectonic environment of the Mesozoic parent rocks in the surrounding source uplifts, rather than the Cenozoic extensional rift setting of the Weixi’nan Sag itself.

Geosciences doi: 10.3390/geosciences16030106

Authors: Haotian Fu Guodong Li Honglin Liu Yongqiang Wu Hongzhi Wang Zhiqiang Liu

Addressing the engineering challenge of creep instability in weakly cemented fractured sandstones within extremely soft coal-bearing formations under long-term loading in western mining areas, using weakly cemented sandstone from a coal mine in Xinjiang as the study subject. This research employs uniaxial graded loading creep tests combined with full-information acoustic emission technology and DIC high-speed strain field observation to investigate the creep deformation patterns (The full name of “DIC” is the three-dimensional high-speed dynamic and static stress–strain analysis system of the DIC strain field measurement and analysis system. For the convenience of expression, this system will be uniformly referred to as DIC in the following text), damage evolution characteristics, and failure mechanisms of sandstone under intact, pre-fabricated 30° fractures, and pre-fabricated 60° fractures. Results indicate: Fractures significantly weaken rock strength and long-term stability. Unfractured specimens primarily exhibit columnar splitting tensile failure, while pre-fractured specimens show pronounced shear failure. Shear cracks accounted for 83.67% of failures in 30° pre-fractured specimens and decreased to 63.44% in 60° pre-fractured specimens. Intact specimens exhibited acoustic emission ringing responses during accelerated creep stages, whereas fractured specimens showed ringing responses as early as the first loading stage. During graded loading, ringing counts in pre-fractured specimens continuously accumulated, with cumulative counts significantly exceeding those of intact specimens. Pre-fabricated cracks induced significant stress concentration effects at the ends, causing failure cracks to propagate preferentially along the crack direction and forming a non-uniform deformation field bounded by the crack. The study revealed the micro-macro evolution patterns of progressive damage during creep in extremely weak fractured rock, providing theoretical support for early warning and control technologies against creep instability in tunnel rock masses of weakly cemented strata in western regions.

Geosciences doi: 10.3390/geosciences16030104

Authors: Yuguo Ni Chenbo Xie Zichen Zhang Jianfeng Chen

Atmospheric visibility nowcasting is vital for safety-critical operations but remains challenging due to complex atmospheric dynamics. We propose a compact stacking ensemble merging a multilayer perceptron (MLP) and gradient-boosted regression trees (GBRT). The model, trained on seven months of minute-scale resolution data with a variability-adaptive filter to suppress sensor noise, employs cross-validation. Results demonstrate that the ensemble achieves its peak performance in the operationally critical low-visibility regime (V < 5 km). This range is particularly significant as it encompasses the Category I and II (CAT I/II) operational thresholds defined by the World Meteorological Organization (WMO) for aviation and surface transportation safety. In this regime, the ensemble yields an R2 of 0.82 and an MAE≈385 m, significantly outperforming single learners during rapid weather transitions. Conversely, in the high-visibility regime (V > 20 km), the explanatory power decreases (R2 of 0.46) due to inherent forward-scattering sensor uncertainties and low aerosol concentrations. Despite these range-specific physical limitations, the model maintains high robustness with narrowly centered residuals. This efficient approach, utilizing cost-effective in situ sensors, is highly suitable for airport and road-weather applications and offers strong potential for multi-site scalability.

Geosciences doi: 10.3390/geosciences16030100

Authors: Qianyun Wang Dingjian Wang Pengju An Qiong Nie Jianlin Lu Zhiyuan Cheng

Model tests are effective for studying the entire deformation and evolution process of reservoir landslides. The sensitivity of similar materials to seepage effects is crucial to the accuracy of landslide model testing. Based on a fuzzy evaluation of in situ sliding zone soil, this study compared three similar materials, using shear tests and microscopic SEM to assess the similarity. The optimal similar material (sliding zone soil: bentonite: standard sand = 50%: 20%: 30%) with a water content of 13.5% and a permeability coefficient of 3.8 × 10−6 cm/s was identified, simultaneously matching physical–mechanical properties and seepage effects. When the proportion of in situ sliding zone soil exceeds that of bentonite, the in situ sliding zone soil dominates the strength. Cohesion depends on interparticle cementation force and water film viscosity. Bentonite modifies these forces in stages, leading to a trend where cohesion (c′) first increases and then decreases with rising water content, while the internal friction angle (φ’) decreases continuously. Model test results indicate the failure mode of reservoir landslides is a three-stage traction-braking failure, evolving from initial shallow deformation to deep progressive failure and finally to overall large-scale instability. The proposed similar material exhibits reliable physical–mechanical and seepage similarity and can be directly applied in physical model tests of reservoir-induced landslides to reproduce the hydro-mechanical coupling behavior of sliding zones.

Geosciences doi: 10.3390/geosciences16030103

Authors: Aichuan Bai Xiangyu Fan Muming Xia Xiao Zou Changchun Zou Panpan Fan

Real-time lithology identification while drilling is widely applied in oil and gas exploration, development drilling, geo-steering, unconventional resource extraction, well logging, and environmental monitoring, enhancing efficiency and accuracy in subsurface operations. This study investigates the frequency characteristics of rock-drilling sounds generated during drilling operations and explores their potential for real-time lithology identification. Experiments were conducted using 8 mm and 14 mm drill bits at both high and low rotational speeds on four types of rock samples: sandstone, limestone, granite, and shaly sandstone. Sound signals were recorded both within the rock and in air using high-fidelity sensors. The results reveal distinct frequency patterns for each rock type, with sandstone exhibiting dominant low-frequency energy, limestone and granite showing broader frequency bands with strong high-frequency components, and shaly sandstone displaying a mix of low- and high-frequency energy. Quadratic polynomial regression models between the Vp or Vs and the peak frequencies of the four distinct rock samples are built, and the corresponding coefficients of determination are 0.9878 and 0.9799. The study also demonstrates that drilling parameters, such as drill bit diameter and revolutions per minute (RPM), significantly influence the frequency distribution of rock-drilling sounds, with larger drill bits and higher RPMs producing broader frequency bands and stronger high-frequency energy. Comparisons between in-rock and in-air recordings show that the latter captures richer high-frequency information, though the overall trends remain consistent. These findings provide an experimental foundation for using rock-breaking sounds as a potential tool for lithology identification during drilling operations. The study highlights the importance of considering rock heterogeneity and drilling conditions when interpreting acoustic data and suggests future work to validate the method in field conditions and integrate advanced data processing techniques.

Geosciences doi: 10.3390/geosciences16030102

Authors: Ethan W. Conley Eric W. Peterson Toby J. Dogwiler John C. Kostelnick

While dissolution dominates the genesis of karst systems, physical erosion processes also play a significant role in their development. Lowering of the water table exposes caves to vadose conditions, reducing roof-supporting buoyancy and potentially leading to catastrophic conduit ceiling failure and cave collapse. The locations and extents of collapse areas are not always identifiable at the landscape surface. High-resolution topographic data derived from LiDAR were used to develop a digital elevation model (DEM) that isolates areas that may have sustained episodes of cave collapse and improves our understanding of past hydrogeological and geomorphological conditions of the system. Cave level delineation from LiDAR data was used to assign elevations to cave entrances. Spatial susceptibility to past collapse was evaluated using a weighted multi-criteria analysis that integrated terrain slope, proximity to mapped cave entrances, and distance to surface streams. Areas identified as having a high likelihood of collapse spatially coincide with cave level contacts and known karst windows and terraces, indicating that this replicated methodology is effective as an initial survey tool for identifying collapse-prone areas in karst landscapes.

Geosciences doi: 10.3390/geosciences16030101

Authors: Fang Liu Dongjun Sun Ting Yang Yuhang Dai

We present a high-resolution 3-D shear-wave velocity model of the Indonesian lithosphere and upper mantle, constructed through a weighted joint inversion of complementary surface wave datasets. Our model integrates teleseismic Rayleigh waves from 387 earthquakes recorded at 31 stations, analyzed using a modified two-plane-wave tomography method, with two years of ambient noise data from 30 stations processed via image transformation techniques. Our results provide new structural constraints on the four principal subduction systems in Indonesia. Along the Sunda–Java Trench, the slab exhibits a systematic along-strike transition from a continuous and well-defined geometry in the west to increasingly disrupted and thickened structures toward the east. This evolution correlates with the subduction of progressively older lithosphere. Beneath the Banda Arc, we image a continuous slab whose dramatic 180° curvature and deep coalescence of distinct segments provide direct evidence for a single-slab rollback and folding origin. In the Molucca Sea region, tomography reveals a shallow low-velocity zone and resolves the complex geometry of an active double-sided subduction system associated with arc–arc collision. Collectively, these findings provide unprecedented constraints on slab segmentation and deformation, highlighting the dominant control of lithospheric age and complex plate interactions on the geodynamic evolution of this exceptional convergent boundary.

Geosciences doi: 10.3390/geosciences16030099

Authors: Hao Li Yanqing Wu Liang Du

When examining ground-penetrating radar (GPR)-based advanced detection ahead of the tunnel face for tunnel constructions, existing numerical forward simulations have not effectively accounted for the actual orientation of the strata and the conditions, limiting their theoretical guidance. In this study, we classify tunnel boring through strata attitudes into horizontal, vertical, positively inclined, reverse inclined, and other anomalous structures. We also consider tunnel faces with different planarity (perfectly smooth or irregular). Using the finite-difference time-domain method with a generalized perfectly matched layer, we simulated 21 forward models for GPR-based advanced detection ahead of the tunnel face. The comparative simulation results indicate that the superposition of reflections from different directions at irregular tunnel faces, lithological interfaces, complicated numerical forward models of typical target geological bodies, making it difficult to distinguish the reflection signals of target geological bodies, and the signal strength in numerical forward modeling profiles with antenna touch with tunnel face is significantly stronger than those without such touch. The flatness of the tunnel face and the close proximity between the antenna and tunnel face are the keys to obtain high-quality original data. These research findings will contribute to improving instruments, data processing, and geologic interpretation in future.

Geosciences doi: 10.3390/geosciences16030098

Authors: Wei Wang Jihong Li Xiuqin Deng Shutong Li Junlin Chen Junli Qiu Xiaoyan Li Youwei Duan

The Chang 8 Member in the Longdong area of the Ordos Basin hosts significant petroleum resources, demonstrating substantial potential for tight oil exploration and development. Astronomical forcing exerts a discernible influence on the evolution of its petroleum system. To elucidate the impact of Milankovitch orbital cycles on organic enrichment and the development of source rocks, reservoirs and cap rocks, we conducted a high-resolution cyclostratigraphic analysis of the Chang 8 Member stratigraphy. This study utilized gamma-ray (GR) well log series as the primary dataset. This lacustrine succession preserves distinct Milankovitch cycles, including ~405 ka long eccentricity, ~125 ka short eccentricity, obliquity, and precession periods, with eccentricity cycles showing particularly strong expression. These diagnostic eccentricity signals provided the framework for delineating high-frequency sequences. Subsequent astronomical tuning and base-level reconstruction constrain the depositional age of the Chang 8 Member to 242.22–241.23 ± 1.4 Ma. During this interval, the lacustrine system exhibited a pronounced trend of base-level fall followed by rise, punctuated by higher-frequency fluctuations. Milankovitch cycles govern the development of high-quality reservoirs and cap rocks and organic enrichment by modulating climate and lake-level fluctuations. These orbital forcings drive weathering processes, control fluvial sediment supply and lacustrine accommodation space, and influence biological productivity. Our results demonstrate a pronounced association between the long eccentricity cycle (~405 ka) and enhanced reservoir quality development, while the short eccentricity cycle (~125 ka) exhibits a stronger correlation with organic matter enrichment, cap rocks, and source rock formation. Ultimately, the interplay of eccentricity cycles jointly governs the formation of the hydrocarbon system within the continental Chang 8 Member.

Geosciences doi: 10.3390/geosciences16030097

Authors: Jianrong Wang Zhipeng Xie Chuandong Xue Wenchang Li Lei Dou Wei Wang Xingwang Song

The Indosinian granitoids of Guangdong Province, South China, record a complex history of crust–mantle interactions during the Triassic assembly of the South China Block (SCB) and Indochina Block (ICB). Integrated zircon U–Pb geochronology, geochemistry, and Sr–Nd–Hf isotopes from these plutons reveal two magmatic episodes: an Early Indosinian phase (253–230 Ma) of large, west-to-east younging batholiths, and a later scattered phase (230–200 Ma). While most granitoids are peraluminous S-types formed by the melting of the Paleoproterozoic crust with limited mantle input (0–30%), the Taibao pluton and its enclaves are anomalous. They are more mafic and record a substantial mantle contribution (40–65%), pointing to focused, high-heat flux magmatism. This spatial and petrogenetic heterogeneity, coupled with the granitoids’ NE–SW trend orthogonal to the collisional zone, cannot be explained by simple crustal thickening. We propose that these features are the direct result of the slab tearing of the subducting Paleo-Tethys oceanic plate, triggered by an oblique collision between the SCB and ICB. This tearing induced asthenospheric upwelling, providing the thermal engine for widespread crustal anatexis and localized mantle melting. Our findings establish slab tearing as a key catalyst for syn-collisional, high-temperature magmatism, offering a unified framework for interpreting lithospheric processes during continental collisions.

Geosciences doi: 10.3390/geosciences16030096

Authors: Lingling Liao Yifei Zhang Yan Li Yinhua Pan

The Yanchang Formation in the Ordos Basin is a key target for continental shale oil exploration in China. Due to its complex geological background and diversified organic inputs, the hydrocarbon generation and accumulation in the lacustrine basin remain to be fully understood. Unlike marine shales rich in Type I kerogen, this lacustrine system is dominated by Type II and III kerogens. In this study, Rock-Eval pyrolysis was performed on lacustrine shales with Type IIa, IIb, and III kerogens to investigate the effect of kerogen type on their hydrocarbon generation and expulsion characteristics. The results reveal that the hydrocarbon generation potential of the Yangchang Formation shale generally follows the order of Type IIa > Type IIb > Type III. Pyrolysis kinetic calculations of the kerogens demonstrate a clear hierarchy of hydrocarbon generation and expulsion among the kerogen types, of which Type II kerogen has better hydrocarbon generation potential, earlier generation timing, and narrower generation window than Type III kerogen. The discrepancy in hydrocarbon generation potential and pyrolysis kinetic behavior is largely attributed to the kerogen components and types, which manifests as a kerogen-type constraint on the hydrocarbon generation and expulsion of shale. Based on the geological mapping of the lacustrine shales in the study area, we propose a “kerogen type-specific” exploration strategy that prioritizes Type IIa-rich intervals in moderate-maturity areas for shale oil exploration, Type IIb as secondary prospects, and Type III in high-maturity areas for shale gas exploration. This study provides a systematic investigation of pyrolysis simulation and hydrocarbon generation and expulsion kinetics on the Yanchang Formation shale, as well as a practical framework for optimizing exploration in analogous lacustrine basins.

Geosciences doi: 10.3390/geosciences16030095

Authors: Vega Perez-Gracia Oriol Caselles Jose Ramón Gonzalez Drigo Viviana Sossa Jaume Clapes

Preventive conservation of historic buildings is crucial to avoid extensive damage, yet assessments are often reactive. Following mortar detachment at the Basilica of Santa María del Pi, this paper presents a diagnosis using Non-Destructive Testing (NDT). The study employed Horizontal-to-Vertical Spectral Ratio (HVSR) for subsoil analysis and Ground Penetrating Radar (GPR) for superstructure inspection. HVSR analysis differentiated fill material from compacted ground, revealing that most of the basilica rests on infilled soil, except the northern corner, suggesting differential settlement risks. Concurrently, GPR survey of vaults and roofs identified internal structures, specifically zones lightened with hollow ceramics, and mapped high-moisture anomalies via wave amplitude and velocity analysis. The study concludes that these methods are complementary, addressing distinct spatial domains. Integrating subsoil characterization with superstructure analysis provided a comprehensive diagnosis essential for long-term maintenance and preservation.

Geosciences doi: 10.3390/geosciences16030094

Authors: Pedro Miguel Callapez Fernando Barroso-Barcenilla Melani Berrocal-Casero José Manuel Brandão Maria José Comas-Rengifo Rúben Domingos Elsa Gomes Fernando Carlos Lopes Mário Miguel Mendes Senay Ozkaya de Juanas Hélder José Pereira Jordi Perez-Cano Ricardo Jorge Pimentel Vanda Faria dos Santos Manuel Segura

A new species of pectinid bivalve, Syncyclonema goyi sp. nov., is described in honour of Professor Antonio Goy, one of the leading stratigraphers who shaped Mesozoic studies in Iberia over the past half century. It represents one of the smaller fossil scallops currently known from the Upper Cretaceous of Europe, alongside a few boreal species previously assigned to the family Entoliidae. The type specimens have orbicular valves, almost smooth, with unequal auricles. The right valve is more convex and bears a well-marked paleal sinus. The sculpture of the shell is weak, exhibiting concentric growth lines and lamellae. However, nearly 90 very small, uniform radial striae are discernible beneath the outer shell layer. This species is frequent in open marine, fine-grained, inner shelf facies of the Tethyan West Portuguese Carbonate Platform, near the main localities of Coimbra, Tentúgal, and Condeixa-a-Nova, in the Baixo Mondego region of West Portugal. It mostly occurs in the upper Cenomanian beds of the Trouxemil Formation, with Euomphaloceras septemseriatum and Vascoceratidae ammonites.

Geosciences doi: 10.3390/geosciences16030093

Authors: Xiang Cheng Shengqian Liu Jinxiong Luo Yan Zhong Dazhi Zhang Shan Sun

The Sinian (Ediacaran) Dengying Formation in the northeastern Sichuan Basin exhibits a significant exploration potential. Nevertheless, the great burial depth of carbonates in the Dengying Formation and the scarcity of drilling data have imposed constraints on in-depth investigations into the evolution of lithofacies paleogeography as well as the primary controlling mechanisms. Through integrated analysis of field outcrops, core and well logging data, the evolution of the lithofacies and paleogeography of the Dengying Formation in the northeastern Sichuan Basin was reconstructed by using 3D stratigraphic forward modeling. The study area is predominantly characterized by platform margin facies and restricted platform facies, comprising four subfacies including microbial (algal) mound, grain shoal, intershoal sea, and intraplatform depression. The microbial (algal) mound and grain shoal subfacies are primarily developed along the western and eastern platform margins, exhibiting a near north–south trend. Scattered mound–shoal complexes and intershoal sea occur within the platform, with localized intraplatform depression zone. During the depositional stage of the Dengying Formation, three primary paleogeomorphic units were developed including the platform margin topographic high zone, intraplatform gentle slope zone, and intraplatform depression zone. During the Deng-1 and Deng-3 periods, sea level rise increased accommodation space, leading to a gradual decline in carbonate productivity and limited development of the mound–shoal complexes. In contrast, during the Deng-2 and Deng-4 periods, sea level decreased, water depth decreased, and carbonate productivity was enhanced, resulting in extensive development of the mound–shoal complexes. The simulation results indicate that carbonate-producing ecosystems thrive when wind blows from 270° W (80% frequency) or 15° N (60% frequency); with an effective water depth of 10–20 m, the elevated carbonate productivity is conducive to the growth of biogenic calcification. Comprehensive analysis suggests that paleogeomorphology, eustatic fluctuations, and paleowind fields collectively control the distribution and evolution of the lithofacies in the Dengying Formation in the northeastern Sichuan Basin. Paleogeomorphology governs the types and distribution of sedimentary facies belts as well as the spatial arrangement of lithofacies. Eustasy determines the magnitude of mound–shoals and their lateral migration. Three-dimensional stratigraphic forward modeling offers a novel approach for reconstructing paleogeographic evolution of carbonate platforms and analyzing key controlling factors, while also enhancing our ability to predict the distribution patterns of mound–shoal complexes.

Geosciences doi: 10.3390/geosciences16030092

Authors: Olga Druzhinina Kseniya Filippova Lyudmila Lazukova Alexandra Golyeva

In this paper, we present the results of a paleoanthracological analysis of the Lateglacial Kulikovo section (eastern Baltic, Kaliningrad region). This is proposed as a new methodological approach to studying the presence of woody taxa in Lateglacial vegetation. Woody vegetation is an important marker of environmental dynamics in post-glacial areas and one of the most important indicators of climate amelioration. Therefore, establishing the time of the appearance of woody vegetation during the Lateglacial period is essential. Paleoanthracological analysis revealed 22 macrocharcoal morphotypes, among which were the following indicators of woody (coniferous and deciduous) vegetation: wood, punky wood, needles, leaf stems, etc. The results indicate an almost continuous local presence of woody species in the study area since the Older Dryas, 14.0 ka. This conclusion is in good agreement with the available data on the presence of phytoliths of conifers and palynological data, indicating that from the end of the Older Dryas up to approximately 12.5 ka, the percentage of arboreal vegetation did not fall below 50% of terrestrial pollen, and over a significant part of the studied time interval it reached 70–80%. Paleoanthracological analysis can serve as both an independent method of studying the emergence of woody vegetation in a certain area and an important addition to the reconstruction of Lateglacial vegetation based on pollen data.

Geosciences doi: 10.3390/geosciences16030091

Authors: Zisong Zhao Shengwei Wu Fucheng Yu Shanping Li Zhiyi Zhao

Mafic microgranular enclaves (MMEs) are widespread in granitic plutons and provide valuable insights into mush–magma mixing processes in crustal magma reservoirs. In this study, we characterize chemical zoning and Sr isotopic compositions of plagioclase in the MMEs, gabbro and host monzogranite from the Late Triassic Xiuyan pluton in East China, to constrain the origin of MMEs and the role of crystal mushes in magma mixing. The MMEs in the Xiuyan pluton are angular and range from centimeters to several meters in size. They exhibit sharp contacts with the host monzogranite and show diverse disequilibrium textures. Plagioclase in MMEs occurs as fine-grained antecryst with normal zoning (An46–66 in the core and An17–29 in the rim). The cores are commonly characterized by coarse sieve textures, patchy zoning, and resorption surfaces at core–rim boundaries. In situ Sr isotopic compositions show subtle but systematic core–rim variations, with (87Sr/86Sr)i increasing slightly from cores (~0.70639) to rims (~0.70664), and rim values overlapping the whole-rock (87Sr/86Sr)i of MMEs. These features suggest that the rim was crystallized from locally hybridized melts produced by interaction between interstitial melts in a basaltic mush and granitic magma. Plagioclase in the gabbro occurs as medium-grained phenocryst with normal zoning (An46–65 in the core and An18–27 in the rim) but shows nearly homogeneous (87Sr/86Sr)i across individual grains (0.70612–0.70637), comparable to whole-rock gabbro values of 0.70623. The plagioclase cores in gabbro also show coarse sieve texture and patchy zoning with the resorption surface in the margin of the core and rim. We interpret the sieve textures in plagioclase cores from both MMEs and gabbro to record partial dissolution during rapid ascent and decompression of an initially H2O-undersaturated, crystal-bearing basaltic magma, during which increased effective water activity reduced plagioclase stability prior to the growth of the rim. Plagioclase in the host monzogranite is medium- to coarse-grained, compositionally homogeneous, and characterized by low An contents (An12–24) and elevated (87Sr/86Sr)i of ~0.70828. We propose that MMEs in the Xiuyan pluton formed when semi-consolidated mafic mush was mechanically disaggregated into angular fragments and subsequently entrained into coexisting granitic melt. This study reveals that MMEs formed by mechanical disaggregation of a semi-consolidated mafic mush into angular fragments, followed by their entrainment into the granitic melts.

Geosciences doi: 10.3390/geosciences16020090

Authors: Hsien-Wang Ou

We develop a minimal thermodynamic model to predict Titan’s surface temperature based on radiative–convective equilibrium and the principle of maximum entropy production (MEP). The model retains only the essential atmospheric constituents: gaseous methane, which absorbs both longwave and near-infrared radiation, and stratospheric haze, which scatters and absorbs solar flux. Subject to Clausius–Clapeyron scaling of methane vapor pressure together with energy balances at the surface, tropopause, and stratopause, the model links the convective flux to the surface temperature, which exhibits a pronounced maximum due to competing radiative effects of tropospheric methane. As the surface warms, enhanced greenhouse effect would strengthen the convection, whereas the rising anti-greenhouse effect would suppress convection. The resulting convective peak corresponds to MEP, which thus selects a surface temperature slightly above methane’s triple point. To assess its long-term evolution, we consider a 20% dimmer early Sun and a hypothetical 20% enrichment of the oceanic methane. Even in combination, they only cool the surface by ~2 K, in sharp contrast to the ~20 K cooling inferred in studies that prescribe haze abundance. This study suggests a critical role of self-adjusting haze in providing the internal degree of freedom necessary for MEP closure, thereby stabilizing Titan’s temperature.

Geosciences doi: 10.3390/geosciences16020089

Authors: Massimo Zecchin Mauro Caffau Octavian Catuneanu

The integration of sedimentological and micropaleontological data in the Zanclean and Gelasian shallow-marine deposits of the Crotone Basin (southern Italy) has allowed documentation of meter-to-decameter-scale high-frequency sequences bounded by wave-ravinement surfaces (WRSs), which in turn are composed of meter-scale sedimentological cycles, referred to as bedsets. In contrast to high-frequency sequences, bedsets have a more subtle appearance, and their boundaries exhibit limited lateral extent compared to WRSs. Moreover, the micropaleontological analyses have allowed the definition of three parameters: distal/proximal (D/P: ratio between distal and proximal benthic foraminifera); fragmentation (Fr: percentage of fragmentation of benthic foraminifera); and P/B (ratio between planktonic and benthic foraminifera). In particular, the D/P and Fr allow to recognize uncertainty intervals containing the maximum flooding surface (MFS) of high-frequency sequences, whereas the P/B documents water-depth changes. Unlike in high-frequency sequences, the D/P, Fr and P/B parameters usually do not show appreciable variations associated with bedsets, confirming that the latter are unrelated to shoreline shifts and water-depth variations, but are rather controlled by minor sediment supply and/or wave regime changes. However, in rare cases, the micropaleontological parameters seem to indicate that subtle transgressive-regressive trends and water-depth variations can also be associated with bedset deposition, alluding to a ‘grey area’ of transition between high-frequency sequences of very small scale and bedsets. Further research is, therefore, needed to constrain the boundary between sedimentology and stratigraphy.

Geosciences doi: 10.3390/geosciences16020088

Authors: Sobhan Emtehani Victor Jetten Cees van Westen Bastian van den Bout

Extreme rainfall events often trigger landslides, debris flows, and sediment-laden floods that cause severe damage in built-up areas, yet sediment deposition is rarely quantified in hazard assessments. This study evaluates the capability of the physically based catchment model LISEMHazard to reconstruct sediment generation, transport, and deposition during Hurricane Maria (2017) in two catchments in Dominica (Coulibistrie and Grand Bay). Simulations were performed at 10 m resolution using rainfall, topography, soil, and land-use data. Model calibration and validation used mapped landslides and debris flows, field measurements of deposition height, and DEMs of Difference (DoDs). LISEMHazard reproduced the general magnitude of sediment volumes and the frequency–area distribution of medium and large landslides but showed poor ability to predict their exact locations and overestimated landslide depth and deposition height. Agreement between modeled and observed debris-flow patterns was good in major channels but weak in minor ones. Sensitivity analysis indicated that soil depth and cohesion dominate uncertainties, whereas saturated hydraulic conductivity and surface roughness exert minimal influence. Despite substantial data and model limitations, physically based modeling remains a practical approach for spatial estimation of sediment deposition needed for risk assessment, structural damage evaluation, and cleanup cost estimation.

Geosciences doi: 10.3390/geosciences16020086

Authors: Wael R. Abdellah Hassan A. M. Abdelkader Atef M. Abu Khatita Mahrous A. M. Ali

This study evaluates the stability and failure probability of rock slopes at Mount Uhud, Madinah, Saudi Arabia, with particular attention to a representative slope in the densely populated southern part. A combined deterministic–probabilistic approach was adopted using a two-dimensional, nonlinear elastoplastic finite element model to capture realistic slope behavior. Uncertainty in key geomechanical parameters—slope angle, cohesion, and internal friction angle—was quantified through Li’s Point Estimate Method, resulting in n3 probabilistic simulations. Slope performance was assessed in terms of both factor of safety (FoS) and probability of failure (Pf). Deterministic analysis yielded a factor of safety of 0.813, while probabilistic simulations produced a factor of safety range between 0.468 and 1.052, with a mean value of approximately 0.73. The corresponding probability of failure was estimated at about 5.16%. Sensitivity analysis indicates that cohesion and internal friction angle exert the strongest influence on stability outcomes. Although the slope shows noticeable sensitivity to reductions in these parameters, the overall probability of failure remains relatively low under current conditions. The results demonstrate that integrating deterministic and probabilistic analyses provides a robust basis for evaluating rock slope reliability in complex geological environments, particularly in rapidly urbanizing mountainous areas such as Mount Uhud.

Geosciences doi: 10.3390/geosciences16020087

Authors: Mihnea Cristian Popa Daniel Constantin Diaconu Adrian Gabriel Simion Ioan Florin Voicu Costache Romulus

The paper addresses the limitations of fragmented and delayed hydrological information systems in supporting timely disaster risk mitigation. The paper introduces the RoWaterAPI, a framework that integrates near real-time hydrological measurements with geospatial analytics to improve awareness during flood-related events. The methodology utilizes open-source technologies, including Django, Kafka, and PostGIS, to support scalable data ingestion and hazard mapping. Initial baseline evaluation under a simulated bursty workload indicates an end-to-end latency of ≈1–3 s and a peak throughput of ≈6000–8500 messages/s. This performance supports real-time alerts for data variations, bridging advanced geoprocessing with user-centered design for public and institutional stakeholders. Ultimately, RoWaterAPI provides a transferable implementation model that can be adapted to any national context facing similar constraints in data fragmentation and operational accessibility.