The Ledong Diapir area of the Yinggehai Basin is characterized by high temperature and strong overpressure background, mud-fluid diapirism, and frequent thermal fluid activity. Based on the geochemical data of rare gas, heat conservation equation, mass balance law, Rayleigh fractionation model and other methods were used to systematically analyze the initial He concentration, thermal driving mechanism, in-situ yield and external flux of helium, as well as the migration and accumulation mechanism of helium in the Ledong Diapir area. The results show that, in the study area, the ³He/⁴He values are (0.002-2.190)×10^-6, and the R/Ra values are 0.01-1.52, indicating the contribution of mantle-derived helium. The CO₂/³He value increases from 1.34×10⁹ to 486×10⁹, indicating that the secondary migration of helium from deep to shallow strata was affected by crust-mantle mixing and degassing effects, with large-scale precipitation of CO₂ and apparent escape of ³He. Under standard conditions, the ratio of ³He to enthalpy is (0.006-0.018)×10^-12 cm³/J, and the heat contribution from the mantle source is low. The in-situ ⁴He yield is (7.66-7.95)×10^-13 cm³/(g·a), and there is a significant external ⁴He flux, which may be related to atmospheric recharge of formation fluid and deep rock-water interaction. The primary migration mode of helium in the study area is mainly advection, while the migration from deep to shallow strata is controlled by the mixing of crust-mantle gases, hydrothermal degassing, and gas-liquid separation. Under the influence of deep thermal fluid, the accumulation mechanism of helium includes deep helium release and efficient migration, lateral migration and trap aggregation, partial pressure balance and strong sealing.

The paper systematically reviews the current applications of various spatial information technologies in CO₂ sequestration monitoring, analyzes the challenges faced by spatial information technologies in CO₂ sequestration monitoring, and prospects the development of spatial information technologies in CO₂ sequestration monitoring. Currently, spatial information technologies applied in CO₂ sequestration monitoring mainly include five categories: eddy covariance method, remote sensing technology, geographic information system, Internet of Things technology, and global navigation satellite system. These technologies are involved in three aspects: monitoring data acquisition, positioning and data transmission, and data management and decision support. Challenges faced by spatial information technologies in CO₂ sequestration monitoring mainly include: selecting spatial information technologies that match different monitoring purposes, different platforms, and different monitoring sites; establishing effective data storage and computing capabilities to cope with the broad sources and large volumes of monitoring data; and promoting collaborative operations by interacting and validating spatial information technologies with mature monitoring technologies. In the future, it is necessary to establish methods and standards for designing spatial information technology monitoring schemes, develop collaborative application methods for cross-scale monitoring technologies, integrate spatial information technologies with artificial intelligence and high-performance computing technologies, and accelerate the application of spatial information technologies in carbon sequestration projects in China.

Based on the practice of waterflooding development in carbonate reservoirs in the Middle East, in order to solve the problem of the poor development effects caused by commingled injection and production, taking the thick bioclastic limestone reservoirs of Cretaceous in Iran-Iraq as an example, this paper proposes a balanced waterflooding development technology for thick and complex carbonate reservoirs. This technology is based on the fine division of development units by concealed baffles and barriers, the combination of multi well type and multi well pattern, and the construction of balanced water injection and recovery system as the core. For the thick carbonate reservoirs in in Iran and Iraq, which are extremely heterogeneous vertically with ultra-high permeability zones of various genesis, and highly concealed baffles an barriers, based on the technologies of characterization and sealing evaluation for concealed baffles an barriers, the balanced waterflooding development technology is proposed, and three types of balanced waterflooding development modes/techniques are formed, namely, conventional stratigraphic framework, fine stratigraphic framework, and deepened stratigraphic framework. Numerical simulations show that this technology can realize a fine and efficient waterflooding development to recover, in a balanced manner, the reserves of thick and complex carbonate reservoirs in Iran and Iraq. The proposed technology provides a reference for the development optimization of similar reservoirs.

A new pore type, nano-scale organo-clay complex pore, was first discovered based on argon ion polishing-field emission scanning electron microscopy, energy dispersive spectroscopy and focused ion-scanning electron microscopy in combination with TOC, R_o, X-ray diffraction etc. in the Cretacesous Qingshankou Formation shale in the Songliao Basin, NE China. Such pore characteristics and evolution study show that: (1) Organo-clay complex pores are developed in the shale matrix and in the form of spongy and reticular aggregates. Different from circular or oval organic pores discovered in other shales, a single organo-clay complex pore is square, rectangular, rhombus or slaty, with the pore diameter generally less than 200 nm. (2) With thermal maturity increasing, elements (C, Si, Al, O, Mg, Fe, etc.) in organo-clay complex change accordingly, showing that organic matter shrinkage due to hydrocarbon generation and clay mineral transformation both affect organo-clay complex pore formation. (3) At high thermal maturity, the Qingshankou Formation shale is dominated by nano-scale organo-clay complex pores with the percentage reaching more than 70%. The spatial connectivity of organo-clay complex pores is significantly better than that of organic pores. It is suggested that organo-complex pores are the main pore space of laminar shale at high thermal maturity and are the main oil and gas accumulation space in the core area of continental shale oil. The discovery of nano-scale organo-clay complex pores changes the conventional view that inorganic pores are the main reservoir space and has scientific significance for the study of shale oil formation mechanics and accumulation laws.

The transtensional faults in the area of Ziyang 3-D seismic survey is an important component of the Central Sichuan Transtensional (strike-slip) Fault System (CSTFS). The in-depth research on the transtensional faults in the Ziyang area is crucial for clarifying the basic hydrocarbon geological conditions of the area and even the central Sichuan Basin, and expanding the oil and gas exploration fields. With well and seismic data of the Ziyang area, through plane-section integrated structural interpretation, 3-D fault framework model building, fault throw analyzing, and balanced profile restoration, it is pointed out that the transtensional fault system in the Ziyang 3-D seismic survey consists of the northeast-trending F_I19 and F_I20 fault zones dominated by extensional deformation, as well as 3 sets of northwest-trending en echelon normal faults experienced dextral shear deformation. Among them, the F_I19 and F_I20 fault zones cut through the Neoproterozoic to Jialingjiang Formation, presenting a 3-D fault plane structure of an "S"-shaped ribbon. And before Permian and during the early Triassic, the F_I19 and F_I20 fault zones underwent at least two periods of structural superimposition. Besides, the 3 sets of northwest-trending en echelon normal faults are composed of small normal faults arranged in pairs, with opposite directions and partially left-stepped arrangement. And before Permian, they had formed almost, restricting the eastward growth and propagation of the F_I19 fault zone. As a conclusion, the F_I19 and F_I20 fault zones communicate multiple sets of source rocks and reservoirs from deep to shallow, and the timing of fault activity matches well with oil and gas generation peaks. Therefore, if there were favorable sedimentary facies and reservoirs developing on both sides of the F_I19 and F_I20 fault belts, the major reservoirs in the Longwangmiao Formation, Qixia Formation, Maokou Formation, and Jialingjiang Formation in this area are expected to achieve breakthroughs in oil and gas exploration.

Based on new data from cores, drilling and logging, combined with extensive rock and mineral testing analysis, a systematic analysis is conducted on the characteristics, diagenesis types, genesis and controlling factors of deep to ultra-deep abnormally high porosity clastic rock reservoirs in the Oligocene Linhe Formation in the Hetao Basin. The reservoir space of the deep to ultra-deep clastic rock reservoirs in the Linhe Formation is mainly primary pores, and the coupling of three favorable diagenetic elements, namely the rock fabric with strong compaction resistance, weak thermal compaction diagenetic dynamic field, and diagenetic environment with weak fluid compaction-weak cementation, is conducive to the preservation of primary pores. The Linhe Formation clastic rocks have a superior preexisting material composition, with an average total content of 90% for quartz, feldspar, and rigid rock fragments, and strong resistance to compaction. The geothermal gradient in Linhe Depression in the range of (2.0-2.6) ℃/100 m is low, and together with the burial history of long-term shallow burial and late rapid deep burial, it forms a weak thermal compaction diagenetic dynamic field environment. The diagenetic environment of the saline lake basin is characterized by weak fluid compaction. At the same time, the paleosalinity has zoning characteristics, and weak cementation in low salinity areas is conducive to the preservation of primary pores. The hydrodynamic conditions of sedimentation, salinity differentiation of ancient water in saline lake basins, and sand body thickness jointly control the distribution of high-quality reservoirs in the Linhe Formation.

Fiber is highly escapable in conventional slickwater, making it difficult to form fiber-proppant agglomerate with propppant and exhibit limited effectiveness. To solve these problems, a novel fiber structure stabilizer (FSS) is developed. Through microscopic structural observations and performance evaluations in indoor experiments, the mechanism of proppant placement under the action of the FSS and the effects of the FSS on proppant placement dimensions and fracture conductivity were elucidated. The results reveal that the FSS facilitates the formation of robust fiber-proppant agglomerates by polymer, fiber, and quartz sand. Compared to bare proppants, these agglomerates exhibit reduced density, increased volume, and enlarged contact area with the fluid during settlement, leading to heightened buoyancy and drag forces, ultimately resulting in slower settling velocities and enhanced transportability into deeper regions of the fracture. Co-injecting the fiber and the FSS alongside the proppant into the reservoir effectively reduces the fiber escape rate, increases the proppant volume in the slickwater, and boosts the proppant placement height, conveyance distance and fracture conductivity, while also decreasing the proppant backflow. Experimental results indicate an optimal FSS mass fraction of 0.3%. The application of this FSS in over 80 wells targeting tight gas, shale oil, and shale gas reservoirs has substantiated its strong adaptability and general suitability for meeting the production enhancement, cost reduction, and sand control requirements of such wells.

The Bohai Bay Basin, as a super oil-rich basin in the world, is characterized by cyclic evolution and complex regional tectonic stress field, and its lifecycle tectonic evolution controls the formation of regional source rocks. The main pre-Cenozoic stratigraphic system and lithological distribution are determined through geological mapping, and the dynamics of the pre-Cenozoic geotectonic evolution of the Bohai Bay Basin are investigated systematically using the newly acquired high-quality seismic data and the latest exploration results in the study area. The North China Craton where the Bohai Bay Basin is located in rests at the intersection of three tectonic domains: the Paleo-Asian Ocean, the Tethys Ocean, and the Pacific Ocean. It has experienced the alternation and superposition of tectonic cycles of different periods, directions and natures, and experienced five stages of the tectonic evolution and sedimentary building, i.e. Middle-Late Proterozoic continental rift trough, Early Paleozoic marginal-craton depression carbonate building, Late Paleozoic marine-continental transitional intracraton depression, Mesozoic intracontinental strike-slip-extensional tectonics, and Cenozoic intracontinental rifting. The cyclic evolution of the basin, especially the multi-stage compression, strike-slip and extensional tectonics processes in the Hercynian, Indosinian, Yanshan and Himalayan since the Late Paleozoic, controlled the development, reconstruction and preservation of several sets of high-quality source rocks, represented by the Late Paleozoic Carboniferous-Permian coal-measure source rocks and the Paleogene world-class extra-high-quality lacustrine source rocks, which provided an important guarantee for the hydrocarbon accumulation in the oil-rich superbasin.

An optimization method of fracturing fluid volume strength was introduced taking well X-1 in Biyang depression of Nanxiang Basin as an example. The characteristic curve of capillary pressure and relative permeability was obtained from history matching between forced imbibition experimental data and core-scale reservoir simulation results and taken into a large scale reservoir model to mimic the forced imbibition behavior during the well shut-in period after fracturing. The study showed that optimization of the SRV fracturing fluid volume strength should meet the requirements of estimated ultimate recovery(EUR), increased oil recovery by forced imbibition and enhancement of formation pressure and fluid volume strength of fracturing fluid should be controlled around a critical value to avoid either insufficiency of imbibition associated oil displacement caused by insufficient fluid amount or increase of costs and potential of formation damage caused by excessive fluid amount. Reservoir simulation results showed that SRV fracturing fluid volume strength positively correlated with well EUR and a optimal fluid volume strength existed, above which the well EUR increase rate kept decreasing. An optimized increase of SRV fracturing fluid volume and shut-in time would effectively increase the formation pressure and enhance well production. Field test results of X-1 well proved the practicality of established optimization method of SRV fracturing fluid volume strength on significant enhancement of shale oil well production.

This study conducted temporary plugging and division fracturing (TPDF) simulation experiments using a true triaxial fracturing simulation system based on a completion simulation of horizontal well with multi-cluster sand jetting perforation. The effects of temporary plugging agent (TPA) particle size, TPA concentration, single-cluster perforation number and cluster number on plugging pressure, multi-fracture diversion pattern and distribution of TPAs were investigated. The results show that a combination of TPAs with small particle sizes within the fracture and large particle sizes within the segment is conducive to increasing the plugging pressure and promoting the diversion of multi-fractures. The addition of fibers can quickly achieve ultra-high pressure, but it may lead to longitudinal fractures extending along the wellbore. The temporary plugging peak pressure increases with an increase in the concentration of the TPA, reaching a peak at a certain concentration, and further increases do not significantly improve the temporary plugging peak pressure. The fracture pressure and temporary plugging peak pressure show a decreasing trend with an increase in single-cluster perforation number. A lower number of single-cluster perforations is beneficial for increasing the fracture pressure and temporary plugging peak pressure, and it has a more significant control on the propagation of multi-cluster fractures. A lower number of clusters is not conducive to increasing the total number and complexity of artificial fractures, while a higher number of clusters makes it difficult to achieve effective plugging. The TPAs within the fracture is mainly concentrated in the complex fracture areas, especially at the intersections of fractures. Meanwhile, the TPAs within the segment is primarily distributed near the perforation cluster apertures which initiated complex fractures.

Based on the latest results of near-source exploration in the Middle and Lower Jurassic of the Tuha Basin, a new understanding of the source rocks, reservoir conditions, and source-reservoir-cap rock combinations of the Jurassic Shuixigou Group in the Taibei Sag is established using the concept of the whole petroleum system, and the petroleum in the coal-measure whole petroleum system is analyzed thoroughly. The results are obtained in three aspects. First, the coal-measure source rocks of the Badaowan Formation and Xishanyao Formation and the argillaceous source rocks of the Sangonghe Formation in the Shuixigou Group exhibit the characteristics of long-term hydrocarbon generation, multiple hydrocarbon generation peaks, and simultaneous oil and gas generation, providing sufficient oil and gas sources for the whole petroleum system in the Jurassic coal-bearing basin. Second, multi-phase shallow braided river delta-shallow lacustrine deposits contribute multiple types of reservoirs (e.g. sandstone, tight sandstone, shale and coal rock) in slope and depression areas, providing effective storage space for the complete physical reservoir formation in coal-measure strata. Third, three phases of hydrocarbon charging and structural evolution, as well as effective configuration of multiple types of reservoirs, result in the sequential accumulation of conventional-unconventional hydrocarbons. From high structural positions to depression, there are conventional structural and structural-lithological reservoirs far from the source, low-saturation structural-lithological reservoirs near the source, and tight sandstone gas, coal rock gas and shale oil accumulations within the source. Typically, the tight sandstone gas and coal rock gas are the key options for further exploration, and the shale oil and gas in the depression area is worth of more attention. The new understanding of the whole petroleum system in the coal-bearing basin will further enrich and improve the geological theory of the whole petroleum system, and provide new ideas for the overall exploration of oil and gas resources in the Tuha Basin.

Based on the geological and geophysical data of Mesozoic oil-gas exploration in Bohai Bay Basin and the recently discovered high-yield volcanic oil and gas wells, this paper methodically summarizes the formation conditions of large- and medium-sized Cretaceous volcanic oil and gas reservoirs in the Bohai Sea. Research shows that the Mesozoic large intermediate-felsic lava and intermediate-felsic composite volcanic edifices in the Bohai Sea are the material basis for the formation of large-scale volcanic reservoirs. The upper subfacies of effusive facies and cryptoexplosive breccia subfacies of volcanic conduit facies of volcanic vent-proximal facies belts are favorable for large-scale volcanic reservoir formation. Two types of efficient reservoirs, characterized by high porosity and medium to low permeability, as well as medium porosity and medium to low permeability, are the core of the formation of large- and medium-sized volcanic reservoirs. The reservoir with high porosity and medium to low permeability is formed by intermediate-felsic lava or the cryptoexplosive breccia superimposed by intensive dissolution. The reservoir with medium porosity and medium to low permeability is formed by intense tectonism superimposed by fluid dissolution. Weathering and tectonic transformation are main formation mechanisms for large and medium-sized volcanic reservoirs in the study area. The “source-reservoir draping type” at the low source is the optimum source-reservoir configuration relationship for large- and medium-sized volcanic reservoirs. There exists favorable volcanic facies, efficient reservoirs and source-reservoir draping configuration relationship on the periphery of Bozhong Sag, and the large intermediate-felsic lava and intermediate-felsic composite volcanic edifices close to strike-slip faults and their branch faults are the main directions of future exploration.

Based on the data of outcrop, core, logging, gas testing, and experiments, the natural gas accumulation and aluminous rock mineralization integrated research method was adopted to analyze the controlling factors of aluminous rock series effective reservoirs in the Ordos Basin, as well as the configuration of coal-measure source rocks and aluminous rock series reservoirs. A natural gas accumulation model was constructed to evaluate the exploration potential of aluminous rock series gas under coal seam in the basin. The results show that the aluminous rock series effective reservoirs in the Ordos Basin is mainly composed of honeycomb-shaped bauxites with porous residual pisolitic and detrital structures, with the diasporite content of greater than 80% and dissolved pores as the main storage space. The bauxite reservoirs are believed to have been formed under a model that levelization controls the material supply, karst paleogeomorphology controls diagenesis, and land surface leaching improves reservoir quality. The hot humid climate and sea level changes in the Late Carboniferous-Early Permian dominated the development of a typical coal-aluminum-iron three-stage stratigraphic structure. The natural gas generated by the extensive hydrocarbon generation of coal-measure source rocks was accumulated in aluminous rock series reservoirs under the coal seam, indicating a model of hydrocarbon accumulation under the source. During the Upper Carboniferous-Lower Permian, the coal-aluminum-iron three-stage stratigraphic structure was developed in the relatively low-lying area on the edge of an ancient land or island in the North China landmass. The aluminous rock series gas reservoirs, which are clustered at multiple points in lenticular shape, are important new natural gas exploration field with great potential in the Upper Paleozoic of North China Craton.

Based on the organic geochemical data and the component and stable carbon isotopic composition of natural gas of the Lower Permian Fengcheng Formation in the western Central Depression of Junggar Basin, combined with sedimentary environment analysis and hydrocarbon generation simulation, the gas-generating potential of the Fengcheng source rock is evaluated, the distribution of large-scale effective source kitchen is described, the genetic types of natural gas are clarified, and four types of favorable exploration targets are selected. The results show that: (1) The Fengcheng Formation is a set of oil-prone source rock, and the retained liquid hydrocarbon is conducive to late cracking into gas, with high gas-generating potential and characteristics of late accumulation; (2) The maximum thickness of Fengcheng source rock reaches 900 m. The source rock has entered the main gas-generating stage in Well Pen-1 western and Shawan sags, and the area with gas generation intensity greater than 20×10⁸ m³/km² is approximately 6 500 km². (3) Around the western Central Depression, highly mature oil-type gas with light carbon isotope composition was identified to be derived from the Fengcheng source rocks mainly, while the rest was coal-derived gas from the Carboniferous source rock; (4) Four types of favorable exploration targets with exploration potential were developed in the western Central Depression which are structural traps neighboring to the source, stratigraphic traps neighboring to the source, shale-gas type within the source, and structural traps within the source.

The previous researches on the subsidence in the southern part of the Ordos Basin during the Triassic period mainly focused on the sedimentary period of the Chang 7 Member, with insufficient understanding of the subsidence in other periods of the initial stage of the basin. Based on a large number of newly added deep well data in recent years, the subsidence of the Ordos Basin in the Mid-late Triassic is systematically studied, and it is proposed that the Ordos Basin experienced two important subsidence events during this depositional period. Through contrastive analysis of the two stages of tectonic subsidence, including stratigraphic characteristics, lithology combination, location of catchment area and sedimentary evolution, it is proposed that both of them are responses to the Indosinian Qinling tectonic activity on the northern edge of the Craton Basin with the feature of fast subsiding. (1) The early subsidence occurred in Chang 10 Member was featured by high amplitude, large debris supply and fast deposition rate, with mainly coarse debris filling and rapid subsidence accompanied by rapid accumulation, resulting in strata thickness increasing from northeast to southwest in wedge-shape. The subsidence center was located in Huanxian-Zhenyuan-Qingyang-Zhengning areas of southwestern basin with the strata thickness of 800-1 300 m. The subsidence center deviating from the depocenter developed multiple catchment areas, until then, unified lake basin has not been formed yet. (2) Under the combined action of subsidence and Carnian heavy rainfall event during the deposition period of Chang 7 Member, a large deep-water depression was formed at slow deposition rate, with the subsidence center coincided with the depocenter basically in the Mahuangshan-Huachi-Huangling areas. The deep-water sediments were 120-320 m thick in the subsidence center, characterized by fine grain mainly. There are differences in the mechanism between the two stages of subsidence. The early one was the response to the northward subduction of the MianLue Ocean and intense depression under compression in Qinling during Mid-Triassic. The later subsidence is controlled by the weak extensional tectonic environment of the post-collision stage during Late Triassic.

Based on the displacement discontinuity method and the discrete fracture unified pipe network model, a sequential iterative numerical method was used to construct a fracturing-production integrated numerical model of shale gas well considering the two-phase flow of gas and water. The model accounts for the influence of natural fractures and matrix properties on the fracturing process and directly applies post-fracturing formation pressure and water saturation to subsequent well shut-in and production simulation, allowing for a more accurate fracturing-production integrated simulation. The simulation results show that the reservoir physical properties have great impacts on fracture propagation, and the reasonable prediction of formation pressure and reservoir fluid distribution after the fracturing is critical to accurately predict the gas and fluid production of shale gas wells. Compared with the conventional method, the proposed model can more accurately simulate the water and gas production by considering the impact of fracturing on both matrix pressure and water saturation. The established model is applied to the integrated fracturing-production simulation of actual horizontal shale gas wells, yielding the simulation results in good agreement with the actual production data, thus verifying the accuracy of the model.

In traditional well log depth matching tasks, manual adjustments are required, which means significantly labor-intensive for multiple wells, leading to low work efficiency. To address this challenge, this paper introduces a multi-agent deep reinforcement learning (MARL) method to automate the depth matching of multi-well logs. This method defines multiple top-down dual sliding windows based on the convolutional neural network (CNN) to extract and capture similar feature sequences on well logs, and it establishes an interaction mechanism between agents and the environment to control the depth matching process. Specifically, the agent selects an action to translate or scale the feature sequence based on the double deep Q-network (DDQN). Through the feedback of the reward, it evaluates the effectiveness of each action, aiming to obtain the optimal strategy and achieve the matching task. Our experiments show that MARL can automatically perform depth matches for well-logs, reducing manual intervention. In the application to the oil field, a comparative analysis of dynamic time warping (DTW), deep Q-learning network (DQN), and DDQN methods revealed that the DDQN algorithm, with its dual-network evaluation mechanism, significantly improves performance by identifying and aligning more details in the well log feature sequences, thus achieving higher depth matching accuracy.

Based on the independently developed true triaxial multi-physical field large-scale physical simulation system of in-situ injection and production, we conducted physical simulation on the long-term injection and production of multiple wells in the hot dry rocks in the Gonghe Basin of Qinghai Province. By virtue of multi-well connectivity experiments, the spatial distribution characteristics of the natural fracture system in the rock samples and the connectivity between fracture and wellbore were clarified. Then, the injection and production wells were selected to conduct the experiments, namely one injection well and two production wells, one injection well and one production well. The variation of several physical parameters in the production well was analyzed, such as the flow rate, the temperature, the heat recovery rate, and the fluid recovery rate. The results show that under the combination of thermal shock and injection pressure, the fracture conductivity was enhanced, and the production temperature showed a downward trend. The larger the flow rate, the faster the decrease. When the local closed area of the fracture was gradually activated, new heat transfer areas were generated, resulting in a lower rate of increase or decrease in the mining temperature. The heat recovery rate was mainly controlled by the extraction flow rate and the temperature difference between injection and production fluid. In addition, as the conductivity of the leak-off channel increased, the fluid recovery rate of the production well rapidly decreased. The influence mechanisms of dominant channels and fluid leak-off on thermal recovery performance were different. The former limits the heat exchange area, while the latter affects the flow rate of the produced fluid. However, both of them were important factors affecting the long-term and efficient development of hot dry rock.

Super oil and gas basins provide the energy foundation for social progress and human development. In the context of climate change and carbon peak and carbon neutrality goals, constructing an integrated energy and carbon neutrality system that balances energy production and carbon reduction becomes crucial for the transformation of such basins. Under the framework of a green and intelligent energy system primarily based on “four news”, new energy, new electricity, new energy storage, and new intelligence energy, integrating a “super energy system” composed of a huge amount of underground resources of coal, oil, gas and heat highly overlapping with abundant wind and solar energy resources above ground, and a regional intelligent energy consumption system with integrated and coordinated development and utilization of fossil energy and new energy, with a carbon neutrality system centered around carbon cycling is essential. This paper aims to select the traditional oil and gas basins as “super energy basins” with the conditions to build world-class energy production and demonstration bases for carbon neutrality. The Ordos Basin has unique regional advantages, including abundant fossil fuel and new energy resources, as well as matching CO₂ sources and sinks, position it as a carbon neutrality “super energy basin” which explores the path of transformation of traditional oil and gas basins. Under the integrated development concept and mode of “coal + oil + gas + new energy + carbon capture, utilization, and storage (CCUS)/carbon capture and storage (CCS)”, the carbon neutrality in super energy basin is basically achieved, which enhance fossil energy supply and contribute to the carbon peak and carbon neutrality goals, establish a modern energy industry and promote green and sustainable development. The pioneering construction of the world-class carbon neutrality “super energy system” demonstration basin in China represented by the Ordos Basin will reshape the new concept and new mode of exploration and development of super energy basins, which is of great significance to the global energy revolution under carbon neutral.

The loose rocks in the Pleistocene Qigequan Formation in the Sanhu Depression of the Qaidam Basin contain biogas, which makes it difficult to characterize structural features, restore sedimentary facies, and predict reservoirs by using P-wave seismic data. To solve this problem, a S-wave 9-component 3D seismic dataset was introduced to seismic sedimentology (i.e., seismic geomorphology and seismic lithology) to build a fourth-order isochronous stratigraphic framework for purpose of sedimentary facies and reservoirs evaluation in the Sanhu region. Under this framework, the techniques of phase rotation, frequency decomposition and fusion, and stratal slicing were utilized to restore sedimentary facies of major marker beds with the guidance of sedimentary model reflected by satellite images. Techniques of seismic attribute extraction, principal component analysis, and random fitting were applied to calculate reservoir thickness and physical parameters of the key sand zones, and the results are satisfactory and confirmed by blind testing wells. The dominant sedimentary facies of major marker beds in the Qigequan Formation within the studied S-wave seismic survey are prodelta and shallow lake. There are lots of channels in the prodelta. In the key sand zone 4-1-4cd, sedimentary facies control reservoir thickness and porosity, and permeability is also affected by diagenesis. In the key sand zone, reservoirs are developed widely, with the biogas in place estimated to be over 79.17×10⁸ m³. Nearly half of the reserves are endowed outside of the known main gas field, which indicates a huge exploration potential.