The development of laminae is one of the typical characteristics of continental shale in faulted lake basins in eastern China. There are three sets of shale layers in the Paleogene Kong 2 Member, Sha 3 Member and Sha 1 Member in the Huanghua Depression,which are formed in different sedimentary environments, thus forming different laminae units. However, the oil-bearing property, reservoir property and compressibility of different types of laminae are different, which affects the exploration and development effect of shale oil. Based on the core samples, wireline logging and mud logging data of three shale successions in the second member of Kongdian Formation, the third member of Shahejie Formation and the first member of Shahejie Formation in the Huanghua Depression of Bohai Bay Basin, on the basis of basic geochemical and rock mineral analysis, combined with AMICSCAN mineral scanning, high resolution scanning electron microscopy, energy spectrum elements, micro-CT scanning and true triaxial hydraulic fracturing simulation and other techniques to carefully characterize the types of laminae in shale, and to clarify the formation environment, reservoir capacity, seepage capacity and fracturing characteristics of different laminated shales. The shale of the second member of the Kongdian Formation in the Huanghua Depression are mainly felsic shale and mixed shale and a small amount of dolomitic shale. The shale of the third member of the Shahejie Formation are mainly mixed shale and felsic shale, while the shale of the first member of the Shahejie Formation are mainly mixed shale and a small amount of dolomitic shale and felsic shale. The second member of the Kongdian Formation shale mainly develops felsic laminae and a small amount of dolomitic laminae and clay laminae. The third member of the Shahejie Formation shale mainly develops dolomitic laminae and clay laminae and a small amount of felsic laminae. The first member of the Shahejie Formation shale mainly develops dolomitic laminae and a small amount of felsic laminae and clay laminae. Clay laminae generally have high organic matter content, acting as a hydrocarbon generation part in the microscopic source-reservoir system, which is beneficial to shale oil enrichment. Felsic laminae and dolomitic laminae usually have high reservoir quality, acting as a reservoir part in the microscopic sourcereservoir system, providing reservoir and storage space for shale oil. Compared with layered and massive shale, shale reservoirs with highfrequency lamination have larger specific surface area, larger filling area of oil and gas, better pore connectivity, and continuous hydrocarbon generation. It has been in an overpressure state. At the same time, the organic acid dissolution feldspar and dolomitic minerals produced in the process of hydrocarbon generation form micron-scale dissolution pores and melodic pores, which can improve the storage and flow capacity of shale reservoirs. The results of physical simulation fracturing experiments show that the laminated felsic shale has the best fracturing effect, followed by the laminated mixed shale, and the massive dolomitic shale has the least fracturing effect.

The newly revised “Mineral Resources Law of the People’s Republic of China” in 2024 (hereinafter referred to as the “New Mineral Resources Law”) has made systematic and reconstructive modifications to the approach of mineral resources management, which has established a whole-chain management system of mineral resources including mining rights, mineral resource exploration and exploitation,ecological restoration of mining areas, mineral resource reserves and emergency, and supervision and administration. Based on a systematic review of the legal provisions related to oil and gas in the New Mineral Resources Law, the content of the provisions has been interpreted from five aspects, i.e., the special protection system for strategic mineral resources, the management model of mining rights transfer registration and administrative licensing, key systems for mining rights management, policy support for exploration and exploitation, and the fulfillment of mining rights holders’ obligations. Meanwhile, the impact of these systems mentioned above on oil and gas mining rights holders has been analyzed. After investigation and data analysis, it is proposed that under the New Mineral Resources Law, oil and gas mining rights holders should implement the special protection system for strategic mineral resources, timely transform the management ideas of oil and gas mining rights transfer, registration, and licensing, properly grasp the key systems of oil and gas management, utilize the supporting policies for oil and gas exploration and exploitation, fulfill the obligations of oil and gas mining rights holders, and promptly offer countermeasures and suggestions for the promulgation of the mineral resources law and regulations.

After over a decade of persistent exploration, China’s shale gas sector has achieved preliminary technological iteration and sustained production growth. However, realizing large-scale commercially viable development remains constrained by scientific and technological bottlenecks. To advance economically efficient extraction and achieve the ‘Chinese Shale Gas Revolution,’ this study clarifies China’s strategic development pathway through comparative analysis of geological characteristics and extraction methodologies between the southern Sichuan Basin and U.S. shale plays. Key findings indicate: ① Sichuan’s shale reservoirs, shaped by multi-phase tectonic events, exhibit heightened structural complexity, significant stress variations, and strong reservoir heterogeneity. Despite superior organic richness (TOC avg. 4.8%) and maturity (R_o >2.5%), critical parameters including porosity (<6%), permeability, and reserves per well trail U.S. benchmarks by 30-50%, constituting inherent constraints to commercial-scale development. ② While U.S. “horizontal drilling + volumetric fracturing” systems offer valuable references, direct replication is infeasible. China must overcome technical barriers in sweet-spot delineation (targeting <5m accuracy),extended-reach lateral drilling (>3500m), and high-efficiency fracturing to establish a geology-adapted technical framework. ③ The U.S. revolution succeeded through project-based management and day-rate contracting, enabling rapid iteration amid high risks. In contrast, China’s fragmented “handover-style” management impedes operational efficiency, necessitating flattened project governance reforms. Recent field practices in Sichuan underscore that the ‘Chinese Shale Gas Revolution’ is imperative for high-quality development. This demands establishing a tailored management system with operational autonomy, pursuing innovation aligned with China’s geological realities, and prioritizing integrated sweet-spot characterization, technological iteration, and 3D reservoir development pilots to drive transformative breakthroughs.

The tight gas discoveries have been made in Benxi Formation and Taiyuan Formation in Shenfu block, Ordos Basin. A better understanding of reservoir characteristics and the main controlling factors is of great significance for the high-efficiency development of coal measure tight sandstone gas. Based on petrology, cast thin section, scanning electron microscopic imaging and high pressure mercury injection test methods, the rock types, reservoir physical properties and diagenesis of tight sandstone reservoirs in Taiyuan Formation–Benxi Formation in Shenfu block have been analyzed, and the main controlling factors affecting reservoir development have been discussed. The study results show that the reservoir lithology of Benxi Formation and Taiyuan Formation is mainly composed of quartz sandstone, lithic quartz sandstone and feldspar lithic sandstone. The main reservoir space types include intragranular dissolution pores, intergranular dissolution pores,intercrystal pores, matrix dissolution pores and micro fractures, followed by primary residual pores, and the throats are mostly fine–medium throats. Compaction and partial cementation had destructive effects on sandstone reservoirs, while dissolution, tectonic activities and chlorite film had constructive effects. The development of sandstone reservoirs in Taiyuan Formation–Benxi Formation was significantly controlled by sedimentary microfacies. The delta underwater distributary channel and tidal channel microfacies were conducive to the development of high-quality reservoirs, and the physical properties of tight sandstone reservoirs were further improved by lithic dissolution, micro-fractures generated by tectonic activities and chlorite films. The high-quality reservoir sand bodies are mainly distributed in the southeastern Xiejiapu and the southern Langanpu areas with underwater distributary channels and tidal channels developed.

The deep palaeohigh in the Persian Gulf Basin controls the development of the giant low-amplitude anticline, which in turn controls the formation of the world-class large oil and gas fields. It is urgent to delineate the distribution characteristics of deep paleohigh and fault in the Persian Gulf Basin and analyze their control on oil and gas distribution. Based on the wavelet analysis of high precision EGM free air gravity data, 36 palaeohighs are identified in Centrel Arabian, Rub’al-Khali and Zagros subbasins. Combining with the formation and evolution of palaeohighs, these palaeohighs are divided into three groups: Precambrian, Late Devonian to Early Carboniferous Epoch, and Mio-Pilocene. The first and second groups of palaeohighs control the development of Precambrian to Devonian anticlinal traps, Devonian unconformity lithologic traps, Periman-Cretaceous anticlinal traps. The third group of palaeohighs control the development of Mio-Pilocene drape anticlinal traps. Based on the reservoir formation conditions in the Persian Gulf Basin, 16 Paleozoic, 26 Jurassic and 16 Cretaceous favorable areas are predicted. This study can provide some reference for deep oil and gas exploration in the Persian Gulf and similar basins.

The exploration and development of Chinese terrestrial shale oil has made significant progress and has become an important field for expanding oil and gas reserves and boosting crude oil production in the petroleum industry.To investigate the development characteristics and formation mechanisms of continental shale lithology and reservoir pore. The main research objects are the mixed shale of the Lower ES3 Submember in the Bonan Subsag of Jiyang Sag and the E1f2 Member in the Gaoyou Sag of the Subei Basin, as well as the matrix shale of the Dongyuemiao Member and Liang2 Member in the Fuxing area of the Sichuan Basin. Based on the observation and description of rock cores, various experimental testing techniques such as whole rock mineral X-ray diffraction, thin section, micro area XRF, high-pressure mercury injection low-temperature nitrogen adsorption joint measurement, micro CT, argon ion polishing scanning electron microscopy, and overburden porosity were used to comprehensively characterize and compare the lithofacies and reservoir pores of continental shale, and to explore the influencing factors and formation mechanisms of reservoir pores. The research results indicate that: Continental shale develops multi-component and multi-scale sedimentary structures, which are controlled by the alternating input of terrestrial and endogenous sources. The sedimentary structure combination types and lithofacies types of mixed shale are more abundant and diverse than those of matrix shale. Bonan is mainly composed of bedded-laminated carbonate mixed shale, bedded felsic mixed shale, laminated carbonate shale, and massive carbonate shale. Gaoyou is mainly composed of laminated felsic mixed shale, laminated carbonate shale, bedded felsic shale, and massive clay mixed shale. Fuxing is mainly composed of massive clay shale, laminated shell carbonate shale, or laminated felsic shale; Based on the differences in pore carriers, a pore division scheme for continental shale oil reservoirs was established, proposing that various inorganic minerals and organic matter components in continental shale can form pores, with carbonate minerals and clay minerals being the most favorable pore forming carriers. Bonan is mainly composed of carbonate mineral pores, Gaoyou is mainly composed of carbonate mineral pores and felsic mineral pores, and Fuxing is mainly composed of clay mineral pores and carbonate mineral pores; High quality lithofacies is the foundation of pore development, and differences in mineral composition, structure, and sedimentary structures can all affect the quality of pore development. Massive clay (mixed) shale and laminated carbonate (mixed) shale have better pore development, while laminated (bedded) felsic (mixed) shale has average pore development, and massive carbonate (mixed) shale has poor pore development; The type and evolutionary sequence of diagenesis are key factors in controlling the formation and preservation of reservoir pores. Rigid mineral particles are stacked in layers or locally mixed to form anti compaction support structures, which are beneficial for pore preservation. Clay mineral transformation and carbonate mineral dissolution are commonly developed pore increasing processes. The inorganic pores of the Bonan and Gaoyou mixed shale are mainly controlled by compaction, recrystallization, and dissolution, and there is basically no development of organic matter pores; The inorganic pores of the Fuxing matrix shale are controlled by compaction, clay mineral transformation, and shell calcite dissolution, while organic matter pores are developed in the asphaltene.

Qingshankou Formation shale oil in Gulong Sag in the northern part of Songliao Basin (referred to as Gulong shale oil) exhibits distinct microscopic migration and differential accumulation characteristics, which affect the distribution and enrichment of retained movable hydrocarbons. The geochemical characteristics of washing oil products and pore structure of sealed and pressurized core sequences from key wells in deep lake area have systematically been tested to clarify the micro distribution characteristics of hydrocarbons and reveal the migration and accumulation mechanism of Gulong shale oil. The study results suggest that Gulong shale in the deep lake area has a grain size of smaller than 63 μm, and four lithofacies are subdivided, i.e., layered clayey shale, laminated mixed shale, laminated felsic shale, and layered calcareous shale. Based on the ranking of shale retention hydrocarbon content, the layered clayey shale with high TOC (>2%) has a high total hydrocarbon content (2.8–13.7 mg/g), and the movable hydrocarbon (2.8–12.5 mg/g) mainly occurs in intercrystal pores of clay minerals smaller than 32 nm. The laminated mixed and felsic shale with medium–high TOC (>1%) has a total hydrocarbon content of 3.8–7.3 mg/g, and the movable hydrocarbon (2.7–6.4 mg/g) mainly occurs in pores with diameters smaller than 8 nm and larger than 64 nm in the mixed laminae. The laminated felsic shale with low TOC (<1%) contains only a small amount of movable hydrocarbon (3.1–4.6 mg/g), mainly occurring in pores with a diameter greater than 64 nm and only a small amount in pores less than 8 nm. The distribution of organic matter laminae and later diagenesis are the key factors for the differential hydrocarbon distribution and accumulation. The organic matters were enriched in clayey laminae, and the generated hydrocarbon was preferentially retained in situ in organic matter pores and clay intercrystal pores. Part of the movable hydrocarbon migrated to felsic laminae or carbonate mineral laminae within source rocks. In areas with strong dissolution and well-developed pores, the movable hydrocarbon migrated on a large scale. While in areas with strong clay and carbonate rock cementation and undeveloped pores, the migration amount of movable hydrocarbon was small. Based on the movable hydrocarbon distribution and accumulation mechanism of Gulong shale oil, it can be further clarified that the high-TOC layered clayey shale has a high oil content but small pore size, which is a resource sweet spot, but the low-TOC laminated felsic shale has a low movable oil content; The medium-hig TOC laminated mixed shale and felsic shale have a high movable oil content, large pore size and good fracability, which is the resource and engineering dual sweet spot.

In the southwestern margin of Ordos Basin, progradation seismic reflection features of Yanchang Formation are extensively observed in 3D seismic profile. By comprehensively using geological data such as well drilling, logging, and core section, well–seismic data has been combined to conduct stratigraphic correlation and division, and analyze the sedimentary evolution of progradation layer, sand body distribution, and oil and gas distribution laws. The following understanding has been obtained: (1) Multi-stage progradation reflection features are observed in the seventh–third members of Yanchang Formation in the southwestern basin margin, which generally reflect the progradation characteristics of water regression and sand progradation. The deposition units are stacked in a tangential oblique pattern towards the lake basin center. After reconstructing a stratigraphic framework of Yanchang Formation, the traditional method of “isopachous” stratigraphic correlation has been changed; (2) The distribution characteristics of the two types of sand bodies in the southwestern basin margin were mainly controlled by the basin bottom shape. The comprehensive study of logging, seismic, and sedimentary facies shows that the upper and lower sections of the progradation layer in Yanchang Formation respectively controlled the distribution of delta front and gravity flow sand bodies, among which the gravity flow sand bodies are favorable reservoir types for large-scale exploration and development; (3) Based on the “two-wide and one-high” seismic information, the distribution of multi-stage deep-water gravity flow sand bodies in the progradation layer has been finely characterized, effectively identifying the distribution range of high-quality reservoirs, and determining that the slope foot sand-rich belt is a favorable area for increasing tight oil reserves on a large scale. The reservoir prediction method based on seismic progradation reflection structure analysis has important guiding significance for the exploration and development of tight oil with similar deep-water sedimentary backgrounds in China.

The Ediacaran represents a key interval in Earth’s surface evolution. Fibrous dolomite, a well-developed carbonate fabric, offers important insights into contemporaneous seawater and pore-water conditions. This review integrates petrographic, crystallographic and geochemical data to assess the origin, distribution, and paleo-environmental significance of fibrous dolomite in the Yangtze Block and Tarim Basin. Primary fibrous dolomites are typically characterized by fibrous morphologies, well-developed growth zoning, and length-slow optical properties, whereas secondary, replacive fibrous dolomites commonly display botryoidal, acicular habits or square terminations, absent growth zoning, and length-fast optical fabrics. Trace element distributions likely provide further constraints on genesis. Multiple fibrous dolomite types have been identified in the Ediacaran Doushantuo (Member I) and Dengying (Member II and IV) formations of the Yangtze Block, as well as in the upper Qigebulake Formation of the Tarim Basin. These include bladed dolomite, fascicular-fast, radial-fast, fascicular-fast and radial-slow dolomite. The former three types are likely to be of replacive origin, whereas fascicular and radial length-slow dolomite likely represent primary precipitates. The Ediacaran seawater characterized by high Mg/Ca ratios, elevated alkalinity and low sulfate promotes the precipitation of fibrous aragonite and highMg calcite precursors. Intense evaporation further increases Mg/Ca, while sulfatereducing bacteria releases Mg²⁺, leads to the increase of pH and alkalinity values, thereby facilitating the nucleation of primary fibrous dolomite. In summary, the Ediacaran fibrous dolomites generally preserve critical geochemical signatures of paleo-seawater and pore-water, and in some cases reflect hydrothermal fluid influence. Their geochemical archives provide robust constraints on the redox state, provenance, and temporal–spatial evolution of Ediacaran Ocean, offering critical evidence for reconstructing Precambrian Ocean chemistry and assessing its environmental controls on early life evolution.

Oil and gas production forecasting is a critical technical approach for optimizing field development strategies and enhancing recovery efficiency. This study systematically reviews the theoretical framework of production decline analysis, conducts a comparative evaluation of conventional empirical models and analytical methods in terms of their theoretical foundations, applicability, and limitations, and highlights innovative applications of machine learning in production prediction for complex reservoirs. The analysis suggests that: ① Traditional methods maintain robustness in conventional reservoirs but exhibit constrained performance in unconventional plays due to strong heterogeneity and multiphase flow nonlinearity; ② Data-driven models demonstrate superior predictive capabilities in unconventional reservoirs through automated feature extraction and spatiotemporal correlation modeling; ③ Physics-informed hybrid models effectively integrate data-driven advantages with physical mechanisms, delivering enhanced reliability under complex conditions and long-term forecasting. The study concludes that artificial intelligence significantly improves prediction accuracy and reliability, with machine learning and deep learning offering novel technical support for complex reservoir development. However, challenges persist in engineering applications, particularly in real-time computation and model interpretability, necessitating further interdisciplinary research to advance intelligent and sustainable development in the oil and gas industry.

The tight sandstone reservoirs in the Ordos Basin have a series of problems, such as poor physical properties, large burial depth, high clay mineral content, and great difficulty in post-pressure drainage. CO₂ fracturing has advantages such as reducing rock breakage, reducing fluid loss and promoting backflow. It is targeted for reservoirs with poor physical properties, high clay content and low pressure coefficient. Therefore, based on the true triaxial simulation of the fracturing modification problem of tight sandstone under three different injection methods: CO₂ pre-injection, CO₂ foam injection, and CO₂ companion injection. The variation law of core fracture pressure and fracture distribution characteristics of tight sandstone reservoirs under different injection methods were analyzed through the similarity criterion, and the difference analysis of core fracturing results under different conditions was compared. And based on the Petrel geological fracturing integrated platform, the numerical simulation study of reservoir fracture propagation under different CO₂ fracturing modes was simulated. It can be known through quantitative experimental analysis that hydraulic fracturing pressure breaking > CO₂ foam > CO₂ injection > CO₂ preinjection. Compared with hydraulic pressure cracks, the CO₂ pre-pressure crack network is the most complex, followed by CO₂ foam, and finally CO₂ injection. The numerical simulation results match it. The variation law of reservoir fracture network parameters with fracturing operation parameters under different injection methods has been clarified. Its understanding provides operational guidance and suggestions for the efficient development of tight sandstone.

The shallow weakly consolidated strata in Bohai Sea area are characterized by new sedimentary age and poor diagenesis, resulting in loose and unformed core samples, and difficulty in conducting conventional rock mechanical tests, which is not conducive to the targeted drilling design in shallow sections. Through comprehensive mineral characterization, physical simulation experiments, and digital core modeling, the mechanical properties and failure mechanisms of shallow strata have systematically been analyzed. By using XRD testing, casting thin section analysis, and nanoindentation technology, the results show that montmorillonite accounts for 48.57% of the clay minerals in the formation, with strong water sensitivity, poor cementation degree, and well developed pores of rock samples. Physical simulation experiments indicate that as the water cut increases from 20% to 30%, the compressive strength of the rock sample decreases from 1.68 MPa to 0.41 MPa, the elastic modulus decreases from 22.1 MPa to 4.81 MPa, the failure mode changes from brittle shear failure to plastic deformation, the number and width of shear zones significantly increase, and the dilatancy effect enhances. The digital core model constructed based on PFC 6.0 is highly consistent with the physical experimental results, which can not only reproduce the dynamic process from elastic deformation to plastic failure of core samples, but also reveal the mechanism of weakening the interparticle bonding force caused by water infiltration through microscopic damage analysis. As a result, a digital core simulation model for shallow weakly consolidated formations in Bohai Sea area has been established for the first time, quantitatively elucidating the degradation law of increasing water cut on rock mechanical properties. The mechanism of water sensitivity induced disasters has been revealed from the dual scale of “macroscopic mechanical response–microscopic damage evolution”, which provides theoretical support for drilling fluid system optimization, wellbore stability control, and sand control process design, as well as new ideas for mechanical study of weakly consolidated formations in sea area.

In Huanjiang–Hongde–Yanwu area in the western margin of Ordos Basin, oil reservoirs were widely developed in the eighth member of the Mesozoic Yanchang Formation (Chang 8 member), with huge reserve amount, which is a favorable replacement resource for further exploration and increasing reserves in the region. However, the electrical resistivity of Chang 8 member oil reservoir generally ranges in 3.0–15.0 Ω·m, and the resistivity ratio between oil layer and water layer is lower than 2, showing low contrast ratio, and leading to great difficulty in oil layer identification. The conventional logging interpretation method has a low accuracy, which is unable to meet the needs of high-efficiency reserve increase and capacity construction. Based on a large amount of well drilling, core data, 3D seismic data, and comparative analysis of logging curves, the genesis of Chang 8 member low-resistivity oil reservoir has been studied from the perspectives of structural evolution and mineralization characteristics. The study results indicate that Chang 8 member low-resistivity oil reservoir in the western margin of Ordos Basin was mainly due to high salinity of formation water and high saturation of bound water. By using an artificial neural network model and variables of six key logging parameters, two sensitive parameters have been introduced, i.e., QRw and PC1, and a machine learning model has been established to prepare a cross plot between them, obtaining good distinguishment results among oil layer, oil–water layer, and water layer, with an accuracy of reservoir fluid type recognition improved to 88.9%.