Search Results (107)

Fraxinus mandshurica (Manchurian ash) is an ecologically and economically valuable hardwood tree native to Northeast Asia, yet its genomic resources remain limited. We assembled its complete chloroplast (cp) genome (155,559 bp) using hybrid PacBio and Illumina sequencing and performed comparative, phylogenetic, and evolutionary analyses. The cp genome exhibits a typical quadripartite structure encoding 132 gene copies, comprising 114 unique genes (80 protein-coding, 30 tRNA, and 4 rRNA genes), with 18 genes duplicated in the inverted repeat (IR) regions. Simple sequence repeat analysis revealed dominance of mononucleotide A/T repeats. Phylogenetic analysis of 53 complete cp genomes strongly supported the monophyly of Oleaceae and resolved F. mandshurica as sister to the North American F. nigra, consistent with previously proposed Miocene intercontinental dispersal scenarios between East Asia and North America. Most protein-coding genes were under strong purifying selection (Ka/Ks << 1), whereas petB, rpl2, and several ndh genes showed elevated Ka/Ks values that are suggestive of altered selective constraint but are based on very few substitutions and are therefore not, on their own, evidence of positive selection. Nucleotide diversity (Pi) analysis identified 15 hypervariable intergenic spacers (mean Pi = 0.067), among which trnM-CAU-rps14, ndhJ-ndhK, and petL-petG represent promising candidate barcode regions requiring further validation. This study provides a high-quality, fully annotated cp genome of F. mandshurica and a valuable genomic resource for future phylogenetic, population genetic, and conservation studies of this important genus. Full article

This paper presents findings from a comprehensive assessment aimed at identifying deep geological storage formations suitable for the secure isolation of chemically active gases, including anthropogenic CO₂. Although Kazakhstan currently lacks operational industrial-scale CO₂ storage sites, high annual emissions exceeding 2 million tonnes are concentrated in its southern region, specifically Almaty city and the surrounding Almaty Region. Despite this pressing need, the precise location, availability, and capacity of potential storage sites in this area remain poorly understood. By synthesizing legacy geological, geophysical, and hydrogeological datasets compiled within the eastern Ili Depression, this study evaluates regional deep saline aquifers for potential CO₂ geological storage under favorable techno-economic conditions. It must be clearly emphasized that this study focuses exclusively on deep groundwater aquifers (saline aquifers). Leveraging historical seismic, drilling, and well-logging data originally acquired for petroleum and water resource exploration, we constrain the stratigraphic architecture and structural framework of prospective storage units. The lithostratigraphic framework of the sedimentary cover in the Ili Basin is established, identifying key reservoir intervals and effective sealing formations. The results indicate that the eastern Ili Depression offers highly favorable conditions for geologic storage, with Permian, Triassic, and Jurassic sedimentary successions reaching thicknesses of up to 1200 m. Reservoir intervals are identified across major stratigraphic units, with potential storage formations accounting for up to 60% of the stratigraphic volume. Specifically, the Miocene–Paleogene and Jurassic intervals host sandstone reservoirs exceeding 10 m in thickness, with porosities reaching up to 30%. Upper Jurassic clayey successions function as effective intraformational seals for Middle Jurassic reservoirs, while Upper Cretaceous clay sequences provide regional caprock integrity for the overlying Neogene–Paleogene sandy intervals. These geological settings satisfy rigorous containment criteria required for secure gas sequestration. These insights into the deep architecture of the Ili Depression elucidate key geological controls governing prospective storage sites, paving the way for future carbon capture and storage (CCS) initiatives in one of Kazakhstan’s most vital economic regions. Full article

Mustelids are a very diverse carnivoran group, boasting the largest number of carnivoran species today, with the most extreme ecological adaptations. Nevertheless, Neotropical Lyncodontini, one Neotropical mustelid subfamily, is one of the least studied from a genetic and evolutionary perspective. The use of small fragments of three mitochondrial (mt) markers (NADH5, 12S rRNA, and D-loop) proved to be very useful for recovering relevant information on the evolutionary history of Neotropical Lyncodontini species of the genera Galictis and Lyncodon. This study used the largest population sample analyzed to date for G. vittata (13 specimens from Guatemala, Colombia, Ecuador, Peru, Bolivia, and French Guiana) and reports for the first time sequences for three mt markers for L. patagonicus other than the mtCyt-b gene. The main results obtained were the following. (1) The haplotype and nucleotide diversity of G. vittata was lower than these statistics measured in other studies of G. cuja in southern and southeastern Brazil. (2) There was evidence from two analyses of a possible population expansion of the female lineages of G. vittata, which began between 635,000 and 370,000 years ago (ya) (mismatch distribution), whereas another procedure (BSP) detected population growth from 500,000 to 80,000 ya, with a population decrease around 40,000 ya. (3) Three genetically distinct groups were detected within G. vittata. One group was in Central America and northern Colombia, another in French Guiana, and the third in the rest of South America. (4) The origin of Neotropical Lyncodontini was older than in other studies (late Miocene, early Pliocene). (6) Some of the analyses detected a closer relationship between L. patagonicus and G. cuja than the latter with G. vittata. This could show that Galictis might be a paraphyletic genus. (7) Many analyses detected that the L. patagonicus haplotypes were the first to originate in situ in South America before the definitive closure of the isthmus of Panama, followed by those of G. cuja, with G. vittata showing the most recent haplotypes. This could indicate that the origin of the current Neotropical Lyncodontini occurred in the south of South America and that colonization occurred towards the north. Full article

Isolated drowned carbonate platforms in the Xisha Area represent critical research archives for deciphering the evolutionary mechanisms of carbonate systems and paleoenvironmental changes within the marginal sea of the northern South China Sea. Nevertheless, existing academic research lacks comprehensive investigations into the sedimentary processes and episodic demise signatures of typical drowned platforms in this region. This study targets the Ganquan Isolated Drowned Carbonate Platform—the largest and best-preserved drowned carbonate platform in the Xisha area. Based on high-resolution 2D multi-channel seismic data and multibeam bathymetric data, this research systematically characterizes the stratigraphic architecture and sedimentary differentiation of the Ganquan Carbonate Platform, and reconstructs its complete Cenozoic evolutionary history via interval velocity inversion, seismic sequence stratigraphic interpretation, sedimentary facies identification, and geomorphological feature analysis. The results reveal that the carbonate succession of the Ganquan Carbonate Platform exhibits prominent vertically zoned interval velocity variations, with two sharp velocity discontinuities identified at the seabed surface and the contact boundary between carbonate rocks and metamorphic basement. Four stratigraphic units are distinguished from top to bottom: seawater column, loose Upper Miocene carbonate deposits, compact Lower–Middle Miocene carbonate strata, and metamorphic basement. Five key Cenozoic seismic boundaries are recognized within the study area, which divide the evolutionary history of the Ganquan Carbonate Platform into four successive episodes: incipient initiation during the Early Miocene, vigorous expansion in the Early–Middle Miocene, transitional decline in the late Middle Miocene, and drowning reworking since the Late Miocene. This study establishes a comprehensive evolutionary model for isolated drowned carbonate platforms in the Xisha region, and advances the theoretical framework governing carbonate platform evolution in marginal seas. Full article

In this study, we sequenced, assembled, and characterized the first complete chloroplast (cp) genome of Eutrema scapiflorum, an alpine species endemic to the Qinghai–Tibet Plateau (QTP). The assembled plastome is 153,041 bp in length and exhibits a typical quadripartite structure, comprising a large single-copy (LSC) region of 83,547 bp and a small single-copy (SSC) region of 17,506 bp, which are separated by two inverted repeats (IRs) of 25,994 bp each. Structurally, the genome encodes 132 unique genes, including 87 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Comparative analysis across eight species revealed that genome size variation is primarily driven by the SSC region. Notably, the IR/SC boundaries in E. scapiflorum are highly conserved, which contrasts with the significant IR expansion observed in Capsella tenella. Furthermore, simple sequence repeat (SSR) analysis identified 78 loci, predominantly mononucleotide A/T repeats located in intergenic spacers. Nucleotide diversity analysis pinpointed accD and ycf1 as the most variable genes. Selection pressure analysis indicated that most genes are under purifying selection, while seven protein-coding genes (ycf2, nadhE, cemA, clpP, psbH, ycf4, nadhB) exhibited signatures of positive selection (Ka/Ks > 1). Subsequently, phylogenomic analyses robustly resolved E. scapiflorum within the tribe Arabideae, showing its closest relationship to Alliaria petiolata. Divergence time estimation dated the split between E. scapiflorum and its closest relative to the middle Miocene (~17.57 Ma). Collectively, these findings provide crucial genomic resources and new insights into the structural evolution, phylogenetic placement, and potential adaptive mechanisms of this alpine species within the Brassicaceae family. Full article

This article analyzes the information provided by the sedimentary sequences of 29 lakes in central Mexico, 10 of which are currently paleolakes. During the Late Quaternary, the lakes of central Mexico experienced environmental changes driven by global and local climatic and geological processes, showing regional trends of wet and dry periods. Paleoenvironmental reconstructions are based on the use of 20 indicators, including diatoms, pollen, geochemistry, mineralogy, granulometry, magnetic susceptibility, and isotopes. Seven major episodes are recognized in the historical evolution of the lakes of central Mexico: i. Late Miocene–Pliocene: A period that includes the formation of large lakes in central Mexico by volcano tectonic activity under a regime of continuous humidity. ii. Pleistocene–Drought and climatic variability of the interglacial period. iii. Drying and successive lacustrine transgression during the Last Glacial Maximum. iv. Spatial climate variability in the Heinrich 1 period. v. Lake regression and expansion of terrestrial vegetation in the Bølling–Allerød period. vi. Transgression of lakes of central Mexico during the Younger Dryas and mid-Holocene periods. vii. Late Holocene: A period that includes lake desiccation influenced by the impact of human activities. The analysis of the data allows us to propose six challenges for the scientific community in future research of central Mexico. Full article

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. Full article

The Beni Snassen belt (northeastern Morocco) hosts several Mississippi Valley-type Pb-Zn ± Cu occurrences localized along the Variscan basement/Lower Liassic carbonate interface within the Atlasic foreland system. This study integrates geological observations with organic petrography and C-O-S-Pb isotopic systematics to constrain the origin of mineralizing fluids, metal source, and ore-forming processes within a basin-scale metallogenic system. The host sequence consists of unmetamorphosed, dolomitized Pliensbachian carbonates with marl interbeds and organic-rich black shales. Mineralization is structurally focused along ENE-WSW and E-W faults and occurs as massive calcite-galena veins, “en échelon” tension gashes, vug fillings, and solution-collapse breccias. Ore-stage calcite exhibits restricted isotopic variability (δ¹³C = −4.7 to +1.2‰; δ¹⁸O = 14.9 to 19.7‰), consistent with rock-buffered basinal fluids and extensive fluid–carbonate interaction. Calculated δ¹⁸O_H2O values indicate precipitation from evolved saline brines variably mixed with meteoric waters. Galena δ³⁴S values (−20.9‰ to +10.3‰) reflect thermochemical sulfate reduction (TSR) under fluctuating redox conditions. Pb isotope compositions define a tight linear cluster between upper crust and orogene growth curves, indicating a predominantly upper crustal metal source, notably Triassic dolerite–diabase lithologies, with a possible contribution from organic-rich black shales. High-reflectance pyrobitumen (VR₀ up to 4%) indicates thermal conditions exceeding those predicted by local burial history, supporting long-distance migration of hydrocarbon-bearing metalliferous fluids from overpressured basin compartments, most plausibly the adjacent Neogene Guercif Basin. Fault reactivation during Late Miocene transtension fostered basin-scale fluid focusing and ore deposition. Hence, the Beni Snassen district represents a basin-integrated MVT system involving crustal metal leaching, organic-assisted metal transport, TSR-mediated sulfur reduction, and structurally focused fluid flow. These results refine metallogenic models for the Atlasic belts and highlight the exploration potential of structurally reactivated foreland basins hosting coupled hydrocarbon-hydrothermal systems. Full article

Anthurium (Araceae) is one of the most species-rich Neotropical genera, yet its infrageneric classification remains unresolved. This study tests the monophyly of the morphologically defined Anthurium sect. Pachyneurium diagnosed by rosulate habit, involute prefoliation, and absence of a collective vein with a focus on Brazilian species. Using target capture sequencing (Angiosperms353 probe set), we generated a phylogenomic dataset for 35 Anthurium species (18 from sect. Pachyneurium) and conducted maximum likelihood and coalescent-based analyses. Our results demonstrate that sect. Pachyneurium is not monophyletic as traditionally circumscribed. Brazilian species previously assigned to the section are recovered in three geographically structured and strongly supported lineages: Amazonian, Atlantic Forest, and Caatinga/Cerrado. The Atlantic Forest lineage is unexpectedly resolved as sister to A. coriaceum (sect. Urospadix), revealing an evolutionary relationship not predicted by morphology. Divergence-time estimates place the origin of crown Anthurium in the Paleocene (~62 Ma), with diversification of the Brazilian lineages occurring during the Miocene (20–3 Ma), coinciding with major geoclimatic events in South America. Our findings indicate that key diagnostic morphological characters are homoplastic and provide a phylogenomic framework for revising the infrageneric classification of Anthurium. By identifying evolutionarily distinct lineages, this study also contributes to prioritizing conservation efforts in threatened Neotropical biomes. Full article

The Tinjar–West Baram Fault in the southern South China Sea is a major NW-trending strike-slip fault that has remained tectonically active since the Oligocene. It forms a key structural boundary between the Zengmu, Beikang, and Nansha Trough basins. Multi-phase strike-slip movements have strongly controlled sediment provenance dispersal pathways, and reservoir development in the Zengmu Basin, yet the sedimentary response to these tectonic processes remains poorly understood. This study integrates 2D seismic profiles to analyze the fault geometry, kinematics, and impact on deep-water sedimentary systems. Results indicate that Oligocene right-lateral motion directed sediment supply from the southwest, mainly sourced from Kalimantan, forming fluvial–deltaic systems with depocenters in the southern basin. Since the Late Miocene, a transition to left-lateral motion reoriented sediment provenance toward the southeast, leading to delta-front complexes and northward migration of depocenters. Strike-slip activity deformation enhanced rock fragmentation and sediment supply, producing fan delta, fluvial, and shallow lacustrine facies near the fault. Associated uplift and subsidence induced relative sea-level fluctuations, resulting in alternating transgressive–regressive sequences. From the Late Eocene to Miocene, the basin evolved from a land–sea transitional system to a deltaic–carbonate complex controlled by the paleo-Sunda River. During the Pliocene–Quaternary, sedimentation was dominated by shallow-marine shelf and semi-deep-marine deposits. Fault-related fracturing significantly enhanced porosity and permeability, creating favorable conditions for hydrocarbon migration and entrapment in both sandstone and carbonate reservoirs. These findings demonstrate a strong coupling between strike-slip fault activity and sedimentary system evolution, providing important insights into sedimentary processes and hydrocarbon potential in strike-slip fault-bounded basins globally. Full article

The scorpion genus Hottentotta Birula, 1908 is widely distributed across Africa and the Middle East, extending to Pakistan, India and Sri Lanka. The processes which resulted in their evolution and diversification across this vast area are poorly understood. The present study investigated the phylogeny and historical biogeography of the genus in the Iranian Plateau and the Zagros Mountains based on nuclear and mitochondrial DNA sequences from four African species, an Arabian species and eight species from the Middle East, most of which are endemic to Iran. Phylogenetic analyses confirmed the monophyly of all species included in the analysis and recovered a clade comprising Iranian and Afro-Arabian species. S-DIVA and BBM analyses demonstrated that the species of Hottentotta occurring in the Iranian Plateau and the Zagros Mountains originated from an African ancestor and then dispersed to their current geographical ranges. Further divergence coincided with the orogeny of the Zagros Mountains and climatic changes during the Miocene epoch. The results support the hypothesis that the Zagros Mountains formed a geographical barrier which promoted vicariance and diversification on the Iranian Plateau. Full article

The stratigraphic evolution of low-latitude carbonate platforms, highly sensitive to sea-level changes, is often poorly constrained due to limited core data and discontinuous depositional records. This study elucidates the evolution of the Meiji Atoll, a representative low-latitude platform in the southern South China Sea (SCS), since the late Miocene, using the reef-penetrating core (Well NK1) from Nansha Island. By integrating facies analysis, sequence stratigraphy, and geochemical proxies, we identified two third-order sequences (SQ1 and SQ2), each comprising transgressive (TST) and highstand (HST) systems tracts. Geochemical data indicate that TSTs were associated with enhanced upwelling and nutrient availability, fostering algal productivity, while HSTs were marked by subaerial exposure. The overall retrogradational stacking pattern of the atoll reflects a dominant control by long-term sea-level rise, superimposed by eustatic fluctuations. Our findings confirm that eustatic sea-level variations were a primary factor controlling the stratigraphic architecture and development of Cenozoic low-latitude carbonate systems. Full article

The depositional environment of the Machów Formation in the central part of the Carpathian Foredeep is still relatively poorly understood. Although lithological variability, facies diversity, and depositional history have been described in many publications, the paleoenvironment of sedimentation and the evolution of individual segments of the sedimentary basin are still not well known. The Miocene complex is difficult to recognize using standard seismic interpretation methods due to cumulative effects of depositional, erosional, and tectonic processes. Progress in science and technology offers new opportunities for the application of high-resolution methods of seismic data interpretation, such as seismostratigraphic interpretation, seismic facies analysis, and seismic geomorphology. The results of seismostratigraphic interpretation of the Machów Formation indicate the presence of numerous depositional sequences of varying thickness and spatial range. The interpretation enabled identification of various types of paleoenvironments, typical for both deeper basin zones (e.g., slope and basin floor fans) and coastal environments. Based on the research conducted, it was concluded that high-resolution 3D seismic data play an essential role in the detection and visualization of lithostratigraphic traps for hydrocarbons, which is important both in exploration and in determining hydrocarbon migration pathways. Full article

A combination of fault and fracture analyses, paleostress reconstructions from calcite twins, and U-Pb dating of syn-kinematic calcite mineralization provides new insights into the Cretaceous–Tertiary tectonic evolution of the Provence fold-and-thrust belt. This approach helped unravel 90 million years of polyphase deformation in this belt, which represents the eastward continuation of the northern Pyrenees. Focusing on three main targets along an NNE-SSW transect oriented roughly parallel to the regional Pyrenean shortening (the southernmost Nerthe range, the Bimont Lake area, and the northern Rians syncline), we date a wide range of scales and natures of deformation structures such as stylolites, veins, mesoscale faults, and major thrust fault zones. The reconstructed long-lasting tectonic history includes (1) the Durancian uplift and related NNE-SSW extension (~110 to 90 Ma); (2) the ~N-S Pyrenean compression related to the convergence then collision between Eurasia and Iberia and the Corsica–Sardinia block (~80 to 34 Ma); the Oligocene E-W to WNW-ESE extension related to the West European Cenozoic Rift System (ECRIS) and the Oligo–Miocene NW-SE to NNW-SSE extension related to the Liguro-Provençal Rifting (LPR); and a middle-late (?) N-S to NW-SE Alpine compression. We show that the Pyrenean shortening in Provence occurred during two main phases, 81–69 Ma and 59–34 Ma, coeval with the inversion of the pre-Pyrenean rift and the main Pyrenean collision, separated by a tectonic quiescence as described in the Pyrenees. Together with the published literature, our U-Pb ages also support the overall northward (forelandward) in sequence propagation of Pyrenean shortening across Provence. Our U-Pb results further allow us to refine the interpretation of local and regional fracture sets and reveal unsuspected polyphase development of fractures sharing a common strike. Beyond regional implications, our study shows that sampling structures of various natures and scales for U-Pb geochronology is probably the most efficient strategy to encompass the entire time interval of deformation in fold-and-thrust belts. Full article

Aeolian deposits are globally recognized as sensitive recorders of Quaternary climate and environmental change, exemplified by the continuous loess sequences of the Chinese Loess Plateau in northern China, which document paleoclimatic and paleoenvironmental evolution since the Miocene. However, such deposits have rarely been confirmed in low-latitude inland regions of southern China. Here we present systematic evidence of aeolian deposition in a low-latitude environment, namely at the Xinlipoding (XLPD) Paleolithic site, situated between the Bose and Bubing Basins in Guangxi, southern China. Using optically stimulated luminescence (OSL), geochemical, and grain-size analyses, we investigate 100 cm thick yellow-brown sandy loam exposed on the hillside of the Bubing Basin. OSL dating constrains its accumulation between 25.3 ± 1.5 ka and 2.7 ± 0.1 ka, spanning the Last Glacial Maximum (LGM) to the late Holocene. Geochemical signatures indicate that the sediments were primarily derived from a nearby terrace in the Bose and Bubing Basins. Grain-size end-member modeling further reveals a mixed alluvial-aeolian origin, comprising both windblown and reworked loess. These findings demonstrate that aeolian dust deposition persisted even in the humid subtropical low-latitude regions of China, recording continuous dust input across glacial–interglacial cycles. The XLPD section thus provides a valuable framework for reconstructing late quaternary environmental change and extends the spatial reach of global aeolian deposition into previously underrecognized regions. Importantly, it also offers a crucial paleoenvironmental context for human occupation in the Bubing Basin from the LGM through the late Holocene. Full article