Search Results (413)

The Ordos Basin hosts abundant lacustrine shale oil resources. Adequately retained hydrocarbons in source rocks, together with favorable mobility, are prerequisites for large-scale shale oil exploitation. Therefore, the quantitative characterization of retained hydrocarbon content and mobility is a core research focus in shale oil exploration and development. This study investigates Chang 7 shale with varying lithofacies and geochemical characteristics. Stepwise pyrolysis and pyrolysis gas chromatography–mass spectrometry (GC–MS) were applied to analyze retained hydrocarbons in different occurrence states, their compositions, and biomarkers. In addition, nuclear magnetic resonance (NMR) combined with CO₂ flooding experiments was conducted, and the collected products under different displacement pressures were analyzed using GC–MS. The aim was to quantitatively examine the variations in expelled oil volume, compositional differences during migration, and occurrence features of shale oil within reservoir micro-pores. The results show the following: (1) Organic-rich shale is characterized by higher proportions of light and medium hydrocarbons, lower heavy fractions, and elevated aromatic hydrocarbon content. In contrast, low-organic-carbon mudstone or siltstone contains more medium and heavy hydrocarbons, with lower light and aromatic fractions. The C13−/C14+ ratio increases with total organic carbon (TOC). (2) In black shale, oil displacement is mainly contributed by mesopores. At low pressures, oil expulsion is difficult and dominated by heavy hydrocarbons. When pressure reaches a threshold, the capillary-bound oil in micropores is released, increasing production and improving oil quality. Muddy siltstone shows higher displacement efficiency than black shale, with contributions from pores of all sizes. At low pressures, its expelled oil volume is larger and lighter than that of black shale. With increasing pressure, the oil yield rises significantly, and medium–large pores produce heavier fractions compared with micropores, likely because light hydrocarbons preferentially enter micropores and are less prone to dissipation. (3) The main controlling factors for shale oil enrichment include retained hydrocarbon content, mobile hydrocarbon fraction, fluidity, and engineering-related parameters. Thick shale layers with high organic matter abundance, high proportions of light–medium hydrocarbons, and favorable porosity–permeability conditions, as well as interbedded siltstone, are enriched in mobile hydrocarbons. Full article

Groundwater–surface water interactions in volcanic hydrogeological systems represent a key process in river dynamics and were preliminarily investigated along a river draining the southern sector of the Sabatini Mountains (central Italy) using an integrated hydrogeological and geochemical approach. Serial discharge measurements, combined with physico-chemical parameters, major ions, stable oxygen isotopes, and radon analyses, reveal marked spatial variability in river–aquifer exchanges along distinct river reaches. The Arrone River exhibits clear differences between upstream, intermediate, and downstream sections, reflecting the relative influence of localized anthropogenic inputs, diffuse groundwater discharge from the volcanic aquifer, and subsurface flow contributions. Upstream reaches are characterized by pronounced modifications in discharge and chemistry, whereas intermediate and downstream reaches show progressive groundwater influence, resulting in distinct geochemical signatures and changes in water quality. Correlation and cluster analyses identify reach-specific processes controlling water composition and support the recognition of gaining and mixed river conditions under varying hydrological regimes. These results constrain a conceptual model in which river behavior is governed by spatially heterogeneous groundwater inflows, modulated by seasonal discharge dynamics and local human pressures. This study highlights the importance of reach-scale investigations for understanding SW–GW interactions in volcanic settings and provides transferable insights relevant to groundwater-dependent river systems. Full article

Efficient simulation of geochemical reactions is critical for predicting the long-term chemical evolution of geological disposal repositories for radioactive waste. In large-scale reactive transport simulations, geochemical equilibrium calculations often represent a major computational bottleneck because they must be repeatedly solved for many spatial cells and time steps. This study investigates the development of machine-learning-based surrogate models that are designed to approximate geochemical equilibrium calculations and thereby significantly accelerate reactive transport simulations while reducing computational resource requirements. Calcite dissolution induced by magnesium-rich fluid inflow is used as a representative test case to evaluate the feasibility and performance of such surrogate models. Training and validation datasets were generated using the IPhreeqc C++ API, enabling the automated execution of a large number of PHREEQC equilibrium simulations across a chemically relevant parameter space. The resulting dataset captures nonlinear relationships between initial aqueous composition and outputs of interest after chemical equilibration, including aqueous species concentrations and amounts of minerals. Fully connected feed-forward neural networks were designed and implemented in TensorFlow to reproduce PHREEQC results, and the influence of key hyperparameters—such as network depth, width, activation functions, learning rate, and batch size—was systematically investigated. The results demonstrate that surrogate model accuracy and training stability are sensitive to hyperparameter selection, even for a relatively simple chemical system. Properly configured neural network architectures reproduce equilibrium geochemical responses with high accuracy and provide a computationally efficient alternative to repeated PHREEQC calculations, highlighting their potential for accelerating large-scale reactive transport modelling workflows. Full article

The Abrolhos Magmatic Province (AMP), situated along the southeastern Brazilian passive margin, comprises a Paleocene–Eocene transitional basalt series of alkaline affinity. Despite the lack of mineral chemistry and thermobarometric estimates, it has long been linked to a classical deep-mantle plume model. This study integrates mineral chemistry, calculations of intensive parameters (P, T, H₂O), geochronology, and geochemical modeling to evaluate an alternative explanation for AMP magmatism. Whole-rock and clinopyroxene compositions from different AMP localities are consistent with parental magmas derived from fertile, pyroxenite-enriched mantle sources that melted under ambient mantle potential temperatures (~1300–1400 °C). Inverse petrological modeling using alphaMELTS and MeltPT, together with trace-element systematics, suggests low degrees of partial melting within asthenospheric domains. These results indicate that shallow (upper-mantle) processes and high mantle fertility were important controls on melt generation. New ⁴⁰Ar/³⁹Ar ages of 24.3–28.4 Ma for southern AMP rocks are also difficult to reconcile with a simple age-progressive evolution of the previously proposed plume model. Taken together, the data support ambient-temperature melting of a fertile mantle as a plausible explanation for Abrolhos magmatism and reduce the need to invoke a classical high-temperature mantle plume as the sole model. Here, we favor a tectonically controlled model, involving localized shallow mantle processes such as edge-driven convection and/or lithospheric delamination as triggers for intraplate magmatism along the South Atlantic margins. Full article

Understanding the development characteristics and controlling factors of organic-rich shales in carbonate platform settings is essential for predicting their distribution and assessing their natural gas exploration potential. However, the mechanisms governing the accumulation of such shales in these specific sedimentary environments remain poorly constrained, and the lack of integrated petrological and geochemical studies limits accurate evaluation of their resource potential. The key objective of this study is to investigate the development characteristics and formation mechanisms of organic-rich shales within intraplatform depressions. To address this objective, we conducted a comprehensive petrological and geochemical analysis of the Cambrian Shuijingtuo Formation organic-rich shale deposits deposited in a carbonate platform setting, particularly from Well EYY3 in Western Hubei, Central Yangtze region. The obtained results indicate that total organic carbon (TOC) contents in the Shuijingtuo Formation can reach up to 4.77%, with a thickness of approximately 9.5 m for shales containing over 2% TOC. Vertically, TOC content exhibits a rapid increase at the base, followed by a gradual decline toward the top, reflecting the evolution of depositional environments. The characteristics of organic-rich shale indicate a significant presence of carbonate minerals, which increase in concentration, alongside tuff lenticular bodies and lithological transition surfaces between tuff and shale. While the longitudinal variation of SiO₂ content in shale is subtle, there is a slight increase in land-sourced clasts and excess silica, and TOC has a significant positive correlation. At the base of the Shuijingtuo Formation, redox parameters, including U-EF and Mo-EF, display a rapid increase followed by a gradual decrease. Conversely, changes in Ni-EF, which indicate paleoproductivity, are less pronounced, and their correlation with TOC is relatively poor. These findings suggest that rapid sea-level rise associated with Cambrian transgressions was the main factor influencing organic matter enrichment in the carbonate platform depressions. This rise supplied nutrients and silica-rich organisms, altering the biological landscape and fostering anoxic conditions in the intraplatform depressions, promoting organic-rich shale formation. As sea levels declined, water circulation became restricted, leading to oxidation of shallow water bodies, decreased paleoproductivity, and shale deposits transitioned to tuff. Therefore, organic-rich shale can also be developed on carbonate platforms, with its formation primarily controlled by fluctuations in sea level. During highstand periods, intraplatform depressions may serve as favorable zones for shale gas exploration. Full article

Sub-sag 21 in the eastern Yangjiang Sag, Pearl River Mouth Basin, South China, contains a thick lacustrine source-rock interval within the lower Wenchang Formation and is a major exploration target on the northern margin of the South China Sea. However, the timing of deposition during the early to middle Eocene remains poorly constrained, and the applicability of quantitative palaeoclimate reconstruction methods in low-latitude lacustrine basins requires further evaluation. In this study, we analyzed mudstones from the lower Wenchang Formation in Well E1. Using cyclostratigraphic constraints, we applied AstroGeoFit to construct an astronomically tuned age model, and combined palynological coexistence analysis with geochemical weathering proxies and linear–regression calibration to quantitatively reconstruct and cross-validate mean annual temperature and mean annual precipitation. Within this time-calibrated framework, we further quantified organic-carbon burial to evaluate the relationship between palaeoclimate evolution and organic-matter enrichment. The AstroGeoFit results indicate that the top of the lower Wenchang Formation in Well E1 is constrained to 44.563 Ma, and that the studied succession spans 50.249–44.563 Ma. Palynological coexistence analysis identifies three palaeoclimate phases within this interval. Method evaluation shows that the temperature reconstruction based on major-element geochemistry agrees well with the pollen-based temperature record, whereas one precipitation reconstruction based on weathering proxies shows the most robust agreement and stability relative to the pollen-based precipitation record. Reconstructed mean annual temperature ranges from 10.77 to 22.20 °C, and reconstructed mean annual precipitation ranges from 1188.27 to 1871.89 mm. Correlation analyses on the tuned timescale show that precipitation is more strongly associated than temperature with organic-matter accumulation parameters, including total organic carbon and organic carbon accumulation rate, indicating that organic carbon burial in the eastern Yangjiang Sag lake basin was mainly controlled by hydrological forcing. During the Early Eocene Climatic Optimum, carbon burial in low-latitude lakes was, therefore, not a simple response to elevated temperature, but instead reflected the integrated effects of precipitation, runoff, stratification, material supply, transport, and preservation. The evolutionary sequence further suggests that early high productivity was diluted by rapid sedimentation, reducing total organic carbon; subsequent cooling, lake deepening, and strengthened stratification enhanced organic matter preservation; and finally, tectonic subsidence together with regional humidification promoted the development and long-term preservation of high-quality lacustrine source rocks. Full article

This study presents an integrated approach for predicting the spatial distribution of gold, copper, and lithium concentrations using machine learning, geostatistical methods, and multivariate geospatial data. The problem is formulated as a spatially dependent multivariate regression task, distinguishing it from traditional classification-based mineral prospectivity approaches. A unified database was developed, incorporating geochemical indicators, geomorphometric terrain parameters, remote sensing data, and spatial coordinates. Correlation analysis with an adaptive threshold was applied to optimize the feature set and improve model robustness. The results show that linear methods are limited in capturing nonlinear relationships, while ensemble methods provide significantly higher predictive accuracy. In some cases, geostatistical methods achieve the best performance, emphasizing the importance of spatial structure. Feature importance analysis indicates that gold prediction is primarily driven by geochemical indicators, spatial coordinates, and terrain characteristics. Results for copper and lithium confirm the general applicability of the proposed approach. Overall, the study demonstrates the effectiveness of combining machine learning and geostatistics for modeling geochemical processes. Full article

Background: Straw application (SP) is an important agronomic practice in sustainable agriculture, yet its effects on arbuscular mycorrhizal (AM) fungal communities in tea plantation soils remain poorly understood. Methods: This study investigated the responses of AM fungi to SP in tea plantations in south Henan, China, by assessing colonization characteristics, community composition, diversity, co-occurrence networks, and soil environmental drivers. Results: SP significantly increased the mycorrhizal colonization rate (MC), by 59.4%. High-throughput sequencing (26,865 sequences and 406 ASVs) revealed that SP reduced the dominance of Claroideoglomus (32.2% to 10.5%) and Glomus (51.01% to 46.7%) while enriching Paraglomus and Acaulospora. Although the α-diversity was unaffected, the β-diversity significantly shifted, indicating community homogenization under SP. Differential taxa analysis confirmed genus-specific responses, and co-occurrence networks showed a simplified topology (nodes: −18.4%; edges: −33.4%) but maintained stability, with increased module specialization (Z_i and P_i). Soil properties explained 80.0% of the variation in AM fungal parameters, with pH and available phosphorus (AP) as key drivers. SP shifted environmental filters from nitrogen/carbon-related factors to metal ions (Al³⁺ and Ca²⁺), altering geochemical conditions. Conclusions: SP selectively reshapes AM fungal communities by altering soil microenvironments and selectively modulating the AM fungal community while maintaining network stability. This study provides new insights into the microbial mechanisms of SP and a basis for sustainable, AMF-based tea plantation management. Full article

Since September 2021, numerous seismic events with spectral peaks below 1 Hz occurred on the island of Vulcano, Italy, 131 years after its last eruption. The local monitoring network recorded microseismicity mostly in the form of months-long swarms, concurrent with anomalous values of other geophysical and geochemical parameters. By applying a machine learning technique (Self-Organizing Maps, SOMs), we obtained an inventory of ~6600 seismic signals, identifying and separating exogenous signals (anthropic noise) from distinct families of events. These families were located below La Fossa Crater (where the last eruption of the volcano happened) from the surface to a depth of 2.2 km b.s.l. Based on the seismic signature and source location of these events, we hypothesize unsealed/sealed processes through a network of shallow fractures favored by fluid pressure. After the return to background values of geochemical and geophysical parameters in 2023, a resumption of microseismicity occurred between May and June 2024. A test application of the SOM to the new data confirmed the non-destructive source of the new recorded signals, which shared families, location, and depths with our previous inventory. This test showed that SOM can be an effective tool for supporting real-time monitoring and warning of future unrest at Vulcano. Full article

Better understanding the controlling factors of shale oil quality including density and viscosity plays a key role in exploring these unconventional pay zones efficiently and profitably. The shale oil extracted from the middle Permian Lucaogou Formation (P₂l) of Santanghu Basin becomes denser and more viscous from the Tiaohu Sag to Malang Sag. It has been proven that oil quality is negatively correlated with saturated hydrocarbon content and positively correlated with aromatic/resin content. However, the underlying controls at the molecular levels are not yet clear. In order to reveal the fundamental controls, shale oil samples with varying density and viscosity were collected from these two sags, and molecular compositions of these samples were analyzed by using gas chromatography–mass spectrometry (GC–MS) for the saturated and aromatic hydrocarbons and electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT–ICR MS) for heteroatom hydrocarbons in resin fraction. Thereafter, correlation analysis was performed between oil density and viscosity and geochemical parameters associated with saturated, aromatic and NSO-containing compounds. The experimental results indicate that the oil thermal maturity levels play a major role, since both density and viscosity present significant negative correlations (correlation coefficient > 0.5) with the maturity parameters of n-alkanes, terpanes, steranes and triaromatic steranes. Organic facies also play a partial role as indicated by the significant positive correlations between density and viscosity and the parameters of tricyclic terpanes, dibenzothiophene/phenanthrene, and methylated phenanthrenes. In resin fraction, density presents better correlations with acid compounds, including O_x (x = 5–9), N₁O_x (x = 0–2) and N₂O₃ species, and viscosity shows better correlations with basic N-containing compounds (N₁O₁, N₁O₃, and N₂O₁ species) and S-containing compounds (N₁S₁ and O₁S₁ species). This indicates that the cross-linking by acid oxygen-containing compounds and the intramolecular and intermolecular forces induced by basic N-containing compounds and sulfur-containing compounds play an important role in directing the P₂l shale oil quality. Moreover, the ratios of specific species with low-to-high double bond equivalents (DBEs) and the homologues with low molecular weight to high molecular weight both present significant negative correlations with density and saturated and aromatic maturity parameters. This highlights the effects of bond cleavage, cyclization and aromatization reactions with elevated thermal maturity in enhancing oil quality in the targeted pay zones. Most P₂l shale oil sources were deposited under the reducing lacustrine setting, containing mainly Type I/II kerogens. Shale oils from Tiaohu Sag are more matured than those from Malang Sag, which is supposed to be responsible for the better oil quality in Tiaohu Sag. This study provides the supporting evidence for regulating shale oil quality in the Santanghu Basin at the molecular levels, and should be helpful in identifying the sweet spots of shale oil plays in this area. Full article

Deep shale gas reservoirs in the southern Sichuan Basin (Weiyuan area) exhibit strong heterogeneity and complex pore-fracture networks. Traditional reservoir evaluation methods struggle to accurately capture their microscale pore characteristics and fracability, thereby restricting efficient development and precise sweet spot prediction. Therefore, integrating digital core technology with geological analysis is essential to systematically quantify key reservoir parameters, including microscale pore structure, mineral composition, and brittleness characteristics. To clarify the controlling factors of high-quality deep shale gas reservoirs in the Weiyuan area and assess their exploration and development potential, we performed digital core analysis at micron to nanometer scales. Three-dimensional digital core models of representative deep shale gas wells were constructed. Integrating mineral composition, geochemical characteristics, and pore space features, we discuss the geological conditions for deep shale gas accumulation and the fracability of horizontal wells, and we delineate favorable shale reservoir zones. The results show that digital core technology enables quantitative and visual characterization of each sublayer of the Longmaxi Formation shale reservoir, including mineral types, laminae types, pore-throat structures, and organic matter distribution. From the Long 11-1 sublayer to the Long 11-4 sublayer, the pore-throat radius, total pore volume, total throat volume, connected pore-throat percentage, and coordination number all gradually decrease. In the eastern Weiyuan area, the siliceous components in deep shale gas reservoirs at the base of the Longmaxi Formation are primarily of both biogenic and terrigenous origin. Due to local variations in the sedimentary environment, terrigenous input contributes significantly to the total siliceous content in this region. Although the Long 11-1 sublayer of the Longmaxi Formation is lithologically classified as mud shale, its particle size and mineral composition more closely resemble those of clayey siltstone or argillaceous sandstone, suggesting considerable potential for reservoir space development. Typical wells in the eastern Weiyuan area exhibit distinct lithological characteristics, including coarser grain sizes, stronger hydrodynamic conditions during deposition, and abundant terrigenous clastic supply. The rigid framework formed by silt- to sand-sized particles effectively mitigates compaction, thereby facilitating the preservation of intergranular pores and microfractures. High organic matter abundance, appropriate thermal maturity, and a considerable thickness of high-quality shale ensured sufficient hydrocarbon supply. The main types of natural fractures are intergranular and grain-edge fractures formed by differences in sedimentary grain size, and bedding-parallel fractures generated by hydrocarbon generation overpressure. Based on reservoir mineral composition, pore characteristics, areal porosity, and pore size distribution identified via digital core analysis, the bottom 0–3 m of the Long 11-1 sublayer is determined to be the optimal target interval. By delineating the microscopic characteristics of the shale reservoir and predicting rock mechanical parameters, a fracability evaluation index was established from digital core simulations. This guides the selection of target layers in deep shale gas reservoirs and optimizes hydraulic fracturing design. Full article

The southern Junggar Basin in Xinjiang is rich in coalbed methane (CBM) resources. Large-scale development is underway in the Sigong River block (SGR block) of the Fukang West Block. Based on an integrated analysis of geological and hydrogeochemical characteristics, this study clarifies the key factors affecting CBM well productivity in the SGR block. Based on gas and water production performance, four distinct productivity types of CBM wells are identified, which are jointly controlled by burial depth, local structural and hydraulic disturbance, and also governed by synergistic interplay between gas content and permeability. The optimal geological combination—comprising the 700–1000 m burial depth, syncline core structure, stagnant hydrodynamic conditions, relatively high gas content, and favorable permeability—collectively contributes to the high-productivity Type I wells with low water production. In contrast, deep coal seams (>1400 m), characterized by reduced gas content and extremely low permeability, correspond to Type IV wells, which exhibit low gas and water production. Type II wells, located in the 1000–1400 m interval, exhibit moderate and variable productivity controlled by the interplay between high gas content and a wide range of permeability. Shallow margins (<700 m) affected by coal combustion and surface water influx produce high-water and low-gas wells (Type III). Geochemical signatures effectively differentiate between these types: closed, stagnant environments (Types I/II) are marked by a Na-Cl-HCO₃/Na-HCO₃-Cl water type, moderate total dissolved solids, and low sodium chloride coefficients, while open hydrodynamic conditions (Type III) are indicated by Na-SO₄-HCO₃ water with high sodium chloride coefficients. A δD-H₂O/δ¹⁸O-H₂O ratio of 7–9, combined with favorable TDS and water type, is identified as a key indicator of high productivity. Based on these relationships, a productivity response index model incorporating critical geological and geochemical parameters was developed. This model provides a practical tool for predicting CBM well performance and targeting sweet spots, offering significant value for exploring geologically and hydrologically complex basins. Full article

Groundwater in Al-Madinah Al-Munawwarah faces considerable challenges from high salinity, elevated TDS, and nitrate contamination, primarily due to urbanization and industrial activities, making ongoing monitoring and management essential for its sustainable use in both drinking water and agriculture. The assessment of groundwater quality was conducted on 44 wells tapping two major aquifers (basaltic and alluvial) in the region, utilizing various geochemical techniques, including ICP-MS, FAAS, and XRF, to evaluate hydrochemical characteristics and identify the primary controlling factors. Key physicochemical parameters, including total dissolved solids (TDSs), electrical conductivity (EC), pH, total hardness (TH), and major ion concentrations, were evaluated. The results indicate that several parameters exceed permissible limits established by Gulf and international standards, reflecting highly saline conditions that could adversely affect drinking water safety and agricultural practices. Elevated nitrate levels and other contaminants indicate a combination of geological processes, including mineral leaching, and anthropogenic activities, such as agricultural runoff. Correlations among various ions reveal complex interactions driven by both natural and human factors. High nitrate and potassium concentrations, particularly in the alluvial aquifer, combined with weak correlations with geogenic ions, indicate anthropogenic inputs. Heavy metals in groundwater were classified into two groups: those within permissible limits (Ag, Ba, Be, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Sb, and U) and those exceeding recommended limits (Zn, Al, As, Se, and Tl). Elevated metal concentrations are primarily attributed to water–rock interactions and the fertilizer use in surrounding agricultural areas. These findings highlight the urgent need for continuous monitoring and proactive groundwater to ensure sustainable and safe use of water resources. Full article

In this study, representative soil profiles developed on clastic rock parent materials in Yunnan Province were investigated to elucidate the formation mechanisms of soil magnetic properties under weakly magnetic parent material conditions and to evaluate the response of magnetic enhancement to chemical weathering and pedogenic differentiation. A combination of environmental magnetic measurements, bulk geochemical analyses, weathering index calculations, and ternary diagram discrimination was applied to characterize soil magnetic behavior, magnetic grain size distribution, and chemical weathering processes. The results show that the clastic rock parent materials exhibit overall low magnetic intensities, with low-frequency magnetic susceptibility (χ_lf) ranging from 2.543 × 10⁻⁸ m³/kg to 595.652 × 10⁻⁸ m³/kg. Under this weakly magnetic background, soils in the study area display pronounced pedogenic magnetic enhancement, with magnetic parameters showing clear and systematic vertical differentiation along soil profiles, indicating that soil magnetic signals are primarily controlled by pedogenesis. The frequency-dependent susceptibility (χ_fd%) generally falls within the range of 5.403%–17.574%, with a mean value of 12.898%, suggesting a substantial contribution from fine-grained magnetic particles. Magnetic grain size diagnostics further indicate that newly formed superparamagnetic (SP) and stable single-domain (SSD) particles generated during pedogenesis dominate the magnetic enhancement signal. The results of the Chemical Index of Alteration (CIA) indicate that approximately 78% of the profiles reach the strong weathering category (CIA > 85), while only 22% fall into the moderate weathering category (CIA: 65–85). Correlation analyses further reveal that grain-size-sensitive magnetic ratios (e.g., χ_fd%, χ_ARM/SIRM) exhibit a strong correspondence with chemical weathering intensity indicators. These findings suggest that, under weakly magnetic parent material conditions, pedogenically induced magnetic enhancement can be more readily identified and quantitatively assessed. The integration of environmental magnetism and geochemical approaches, therefore, provides a robust framework for investigating pedogenic differentiation and supports high-resolution paleoenvironmental reconstruction in regions dominated by weakly magnetic parent materials. Full article

Hydrocarbon resource potential evaluation represents the primary and core component of whole petroleum system studies. However, compared with the substantial progress achieved in understanding hydrocarbon generation mechanisms, quantitative assessments of hydrocarbon generation amounts from source rocks in the Songliao Basin remain relatively limited. Given that the genetic method is capable of comprehensively reflecting both the intrinsic hydrocarbon generation potential and conversion efficiency of source rocks and is supported by robust geological principles, this study was conducted within a genetic framework. Stratigraphic data and lithological descriptions from more than 2000 wells in the northern Songliao Basin, logging data from 387 wells, and measured basic geochemical data from 201 wells were integrated. Combined with the ΔlogR method, original hydrocarbon generation potential restoration techniques, and results from thermal simulation experiments, the planar distributions of key geochemical parameters of the first member of the Qingshankou Formation were systematically characterized. On this basis, the hydrocarbon generation potential and total hydrocarbon generation amounts of different structural units within the Songliao Basin were quantitatively evaluated. The results indicate that the cumulative hydrocarbon generation of the first member of the Qingshankou Formation reached approximately 506.55 × 10⁸ t. Among the structural units, the Qijia–Gulong Sag contributed 266.13 × 10⁸ t, the Sanzhao Sag 132.71 × 10⁸ t, the Longhupao Terrace 66.81 × 10⁸ t, and the Daqing Placanticline 40.90 × 10⁸ t. These results demonstrate significant heterogeneity in hydrocarbon generation capacity among different structural units, with the Qijia–Gulong Sag identified as the most important hydrocarbon generation center in the study area. This study provides a critical quantitative foundation for whole petroleum system research in the northern Songliao Basin. It not only supplies essential data support for subsequent resource apportionment of conventional and shale hydrocarbons but also offers important constraints for analyses of reservoir-type distribution and hydrocarbon accumulation mechanisms. Full article