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The lower Cambrian Qiongzhusi (Є1q) shale in the Sichuan Basin, formerly considered a source rock, recently achieved high gas production (7.388 × 105 m3·d−1) from well Z201 in the Deyang–Anyue rift trough (DART), marking an exploration breakthrough of the world’s oldest industrial shale gas reservoir. However, the shale gas enrichment mechanism within the DART is not fully understood. This study reviews the formation of the Qiongzhusi shale gas reservoirs within the DART by comparing them with cotemporaneous deposits outside the DART, and several findings are presented. The gas production interval was correlated with the main phase of the Cambrian explosion (lower Cambrian stage 3). In the early Cambrian ecosystem, dominant animals likely accelerated the settling rates of organic matter (OM) in the upper 1st member of Є1q (Є1q12) by feeding on small planktonic organisms and producing larger organic fragments and fecal pellets. High primary productivity and euxinic conditions contributed to OM enrichment in the lower 1st member of Є1q (Є1q11). Additionally, shale reservoirs inside the DART demonstrated better properties than those outside in terms of thickness, brittle minerals, gas content, and porosity. In particular, the abundant OM pores inside the DART facilitated shale gas enrichment, whereas the higher thermal maturity of the shales outside the DART possibly led to the graphitization and collapse of some OM pores. Meanwhile, the overpressure of high-production wells inside the DART generally reflects better shale gas preservation, benefiting from the shale’s self-sealing nature, “upper capping and lower plugging” configuration, and limited faults and microfractures. Considering these insights, we introduced a “ternary enrichment” model for the Qiongzhusi shale gas. Although the current high gas production of Z201 was found at the reservoir 3, two additional reservoirs were identified with significant potential, thus suggesting a “multilayer stereoscopic development” strategy in future shale gas exploration within the DART.

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, 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 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 energy supply and contribute to the carbon peak and carbon neutrality goals, establish a modern energy industry and promote regional 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 neutrality.

The essence of energy system transition is the “energy revolution”. The development of the “resource-dominated” energy system with fossil energy as the mainstay has promoted human progress, but it has also triggered energy crisis and ecological environment crisis, which is not compatible with the new demands of the new round of scientific and technological revolution, industrial transformation, and sustainable human development. It is in urgent need to research and develop a new-type energy system in the context of carbon neutrality. In the framework of “technique-dominated” new green and intelligent energy system with “three new” of new energy, new power and new energy storage as the mainstay, the “super energy basin” concepts with the Ordos Basin, NW China as a representative will reshape the concept and model of future energy exploration and development. In view of the “six inequalities” in global energy and the resource conditions of “abundant coal, insufficient oil and gas and infinite new energy” in China, it is suggested to deeply boost “China energy revolution”, sticking to the six principles of independent energy production, green energy supply, secure energy reserve, efficient energy consumption, intelligent energy management, economical energy cost; enhance “energy scientific and technological innovation” by implementing technique-dominated “four major science and technology innovation projects”, namely, clean coal project, oil production stabilization and gas production increasing project, new energy acceleration project, and green-intelligent energy project; implement “energy transition” by accelerating the green-dominated “four-modernization development”, namely, fossil energy cleaning, large-scale new energy, coordinated centralized energy distribution, intelligent multi-energy management, so as to promote the exchange of “two 80%s” in China's energy structure and construct the new green and intelligent energy system.

Carbon dioxide storage and utilization has become an inevitable trend and choice for sustainable development under the background of global climate change and carbon neutrality. Carbon industry which is dominated by CO2 capture, utilization and storage/ CO2 capture and storage (CCUS/CCS) is becoming a new strategic industry under the goal of carbon neutrality. The sustainable development of carbon industry needs to learn from the experiences of global oil and gas industry development. There are three types of “carbon” in the earth system. Black carbon is the CO2 that has not been sequestered or used and remains in the atmosphere for a long time; grey carbon is the CO2 that has been fixed or permanently sequestered in the geological body, and blue carbon is the CO2 that could be converted into products for human use through biological, physical, chemical and other ways. The carbon industry system covers carbon generation, carbon capture, carbon transportation, carbon utilization, carbon sequestration, carbon products, carbon finance, and other businesses. It is a revolutionary industrial field to completely eliminate “black carbon”. The development of carbon industry technical system takes carbon emission reduction, zero carbon, negative carbon and carbon economy as the connotation, and the construction of a low-cost and energy-efficient carbon industry system based on CCUS/CCS are strategic measures to achieve the goal of carbon neutrality and clean energy utilization globally. This will promote the “four 80%s” transformation of China's energy supply, namely, to 2060, the percentage of zero-carbon new energy in the energy consumption will be over 80% and the CO2 emission will be decreased by 80% to ensure the carbon emission reduction of total 80×108 t from the percentage of carbon-based fossil energy in the energy consumption of over 80%, and the percentage of CO2 emission from energy of over 80% in 2021. The carbon industry in China is facing three challenges, large CO2 emissions, high percentage of coal in energy consumption, and poor innovative system. Three strategic measures are proposed accordingly, including: (1) unswervingly develop carbon industrial system and ensure the achievement of carbon neutrality as scheduled by 2060; (2) vigorously develop new energy sources and promote a revolutionary transformation of China's energy production and consumption structure; (3) accelerate the establishment of scientific and technological innovation system of the whole CO2 industry. It is of great significance for continuously optimization of ecological environment and construction of green earth and ecological earth to develop the carbon industry system, utilize clean energy, and achieve the strategic goal of global carbon neutrality.

Under the requirements of China's strategic goal of ''carbon peaking and carbon neutrality'', as a renewable, clean and efficient secondary energy source, hydrogen benefits from abundant resources, a wide variety of sources, a high combustion calorific value, clean and non-polluting, various forms of utilization, energy storage mediums and good security, etc. It will become a realistic way to help energy, transportation, petrochemical and other fields to achieve deep decarbonization, and will turn into an important replacement energy source for China to build a modern clean energy system. It is clear that accelerating the development of hydrogen energy has become a global consensus. In order to provide a theoretical support for the accelerated transformation of hydrogen-related industries and energy companies, and provide a basis and reference for the construction of ''Hydrogen Energy China'', this paper describes main key technological progresses in the hydrogen industry chain such as hydrogen production, storage, transportation, and application. The status and development trends of hydrogen industrialization are analyzed, and then the challenges faced by the development of the hydrogen industry are discussed. At last, the development and future of the hydrogen industry are prospected. The following conclusions are achieved. (1) Hydrogen technologies of our country will become mature and enter the road of industrialization. The whole industry chain system of the hydrogen industry is gradually being formed, and will realize the leap-forward development from gray hydrogen, blue hydrogen to green hydrogen. (2) The overall development of the entire hydrogen industry chain such as hydrogen production, storage and transportation, fuel cells, hydrogen refueling stations and other scenarios should be accelerated. Besides, in-depth integration and coordination with the oil and gas industry needs more attention, which will rapidly promote the high-quality development of the hydrogen industry system. (3) The promotion and implementation of major projects such as ''north-east hydrogen transmission'', ''west-east hydrogen transmission'', ''sea hydrogen landing'', and utilization of infrastructures such as gas filling stations, can give full play to the innate advantages of oil and gas companies in industrial chain nodes such as hydrogen production and refueling, etc., which can help to achieve the application of ''oil, gas, hydrogen, and electricity'' four-station joint construction, form a nationwide hydrogen resource guarantee system, and accelerate the planning and promotion of the ''Hydrogen Energy China'' strategy.

Energy is the basis of human development and the impetus of society progress. There are three sources of energy: energy of celestial body outside the Earth, the Earth energy and energy of interaction between the Earth and other celestial bodies. Meanwhile, there are three scales of co-evolution: the evolution of the Sun-Earth-Moon system on an ultra-long time scale has provided energy sources and extra-terrestrial environmental conditions for the formation of the Earth system; the evolution of the Earth system on a long time scale has provided the material preconditions such as energy resources and suitable sphere environment for life birth and the human development; on a short time scale, the development of human civilization makes the human circle break through the Earth system, expanding the extraterrestrial civilization. With the co-evolution, there are three processes in the carbon cycle: inorganic carbon cycle, short-term organic carbon cycle and long-term organic carbon cycle, which records human immoderate utilization of fossil energy and global sphere reforming activities, breaking the natural balance and closed-loop path of the carbon cycle of the Earth, causing the increase of greenhouse gases and global climate change, affecting human happiness and development. The energy transition is inevitable, and carbon neutrality must be realized. Building the green energy community is a fundamental measure to create the new energy system under carbon neutrality target. China is speeding up its energy revolution and developing a powerful energy nation. It is necessary to secure the cornerstone of the supply of fossil energy and forge a strong growing pole for green and sustainable development of new energy. China energy production and consumption structure will make a revolutionary transformation from the type of fossil energy domination to the type of new energy domination, depending on a high-level self-reliance of science and technology and a high-quality green energy system of cleaning, low-carbon, safety, efficiency and independence. Energy development has three major trends: low-carbon fossil energy, large-scale new energy and intelligent energy system, relying on the green innovation, contributing the green energy and constructing the green homeland.

Studying the accumulation rules of organic matter (OM) in paleo-ocean sediments can not only enhance our understanding of how OM becomes enriched in ancient oceans but also provide guidance for the exploration of shale gas in unconventional shale strata. A breakthrough has been made in shale gas exploration in the early Cambrian Qiongzhusi Formation in South China. However, less attention has been paid to the intraplatform basin of the Yangtze Platform, and the factors controlling organic matter enrichment in this special region remain unclear. This study focuses on a continuous drilling core across the full well section of the Qiongzhusi Formation in the intraplatform basin of the Yangtze Platform. Through the comprehensive analysis of total organic carbon (TOC), major and trace elements, and Mo isotopes, this study investigates the controlling factors for OM enrichment with δ98/95Mo ratios utilized to identify the existence of euxinic bottom water. The examined 240 m long core can be divided into four units, where the TOC values of the lower Units 1 and 2 (0.2–5.0 wt.%) average higher than the upper Units 3 and 4 (0.2–2.5 wt.%). Redox indicators (U/Th, Ni/Co, EF(Mo)—EF(U)) indicate an increasing oxidation of bottom waters from the bottom upwards. δ98/95Mo data further confirm the presence of weakly euxinic conditions in Units 1 and 2, addressing the ongoing controversy surrounding bottom water redox environments. Primary productivity indicators (Ni/Al, Cu/Al) suggest a relatively low average productivity level within the intraplatform basin. The upwelling indicators EF(Co) * EF(Mn) of different profiles in the Yangtze Platform suggest that low productivity within the intraplatform basin can be mainly attributed to the absence of upwelling. Consequently, this study proposes an organic matter enrichment mechanism for the Qiongzhusi Formation in the intraplatform basin, which emphasizes the significance of the redox environment in the formation of high-quality hydrocarbon source rocks in restricted environments that lack upwelling, setting it apart from the deep ocean. These findings have the potential to provide valuable insights for the exploration of high-quality hydrocarbon source rocks in other similar regions.

Global climate change caused by geological processes is one of the main causes of the 5 global mass extinctions in geological history. Human industrialization activities have caused serious damage to the ecosystem, the greenhouse effect of atmospheric CO2 has intensified, and the living environment is facing threats and challenges. Carbon neutrality is the active action and common goal of mankind in the face of the climate change crisis, therefore, probing into its theoretical and technological connotation, scientific and technological innovation system has far-reaching significance and broad prospects. Studies indicate that (1) Carbon neutrality reflects the theoretical connotations of “energy science” and “carbon neutrality science”, including technical connotations of carbon emission reduction, zero carbon emission, negative carbon emission, and carbon trading. (2) Carbon neutrality spawns new industries such as carbon industry centering on CO2 capture, utilization, and storage (CCUS, or CO2 capture and storage CCS), and hydrogen industry centering on green hydrogen. “Gray carbon” and “black carbon” are the two application attributes of CO2. “Carbon+”, “Carbon−”, and “Carbon=” are three carbon-neutral products and technologies. (3) China faces three major challenges in achieving the goal of carbon neutrality: first, energy transition is large in scale and the cycle is short; Second, there are many problems in the process of energy transition, such as security uncertainties, economic utilization, and unpredictable disruptive technologies; Third, after transition, we may face new key techno-logical “bottlenecks” and “broken chain” of key mineral resources. (4) Based on current knowledge to predict the top 10 disruptive technologies and industries in the energy field: underground coal gasification, in-situ conversion process of medium and low-mature shale oil, CCUS/CCS, hydrogen energy and fuel cells, bio-photovoltaic power generation, space-based solar power generation, optical storage smart micro-grid, super energy storage, controllable nuclear fusion, wisdom energy Internet. Five strategic projects will be implemented, including energy conservation and efficiency improvement, carbon reduction and sequestration, scientific and technological innovation, emergency reserve and policy support. (5) In the future, different types of energy will have different orientations. Coal will play the role of ensuring the national energy strategy “reserve” and “guarantee the bottom line”. Petroleum will play the role of ensuring national energy security “urgent need” and the “cornerstone” of raw materials in people's livelihood. Natural gas will play the role in ensuring national energy “safety” and “best partner” of new energy. New energy will play the role in ensuring the “replacement” and “main force” of the national energy strategy. (6) Carbon neutrality is a major practice of the green industrial revolution, carbon reduction energy revolution, and ecological technology revolution, which will bring new and profound changes to human society, the environment and the economy. (7) Carbon neutrality needs to follow the four principles of “disruptive breakthroughs in technology, guarantee of energy security, realization of economic feasibility, and controllable social stability”. We should rely on technological innovation and management changes to ensure the realization of national energy “independence” and carbon neutrality goal, and make China's contribution to the construction of a livable earth, green development, and ecological civilization.

In geological history, one major life explosion and five mass extinction events occurred. These major biological and environmental events affected the evolution of the Earth ecosystem and controlled the formation of organic-rich strata. The life explosion occurred in Cambrian and the five mass extinction events happened at the end of Ordovician, Late Devonian, end of Permian, end of Triassic, and end of Cretaceous, respectively. They are corresponded to the formation of multiple suites of organic-rich strata globally, which are crucial to the formation, evolution and distribution of the fossil energy on Earth. China’s energy is characterized by “unlimited new energy, rich in coal but insufficient in oil and gas “, and it is determined to rely on new energy sources to achieve” energy independence “and carbon neutrality. From the perspective of the Earth system evolution, we investigate the multiple relationships between energy and Earth, energy and environment, as well as energy and human beings, and carry out comprehensive research on energy. Energy science refers to the science of studying the various energy sources formation and distribution, evaluation and selection, production and utilization, orderly replacement, development prospects, etc. in temporal and spatial scales based on the evolution of the Earth system. The connotation of energy science includes three core contents: (1) The relationship between the Earth and energy, including the formation of energy in the Earth system and the feedback of energy consumption to the Earth’s climate and environment; (2) The relationship between the Earth environment and the human beings, including the Earth environment breeding human beings and human activities transforming the earth environment; (3) The relationship between the energy and the human beings, including the development of energy technology by human beings and the progress of human society driven by energy utilization. The energy science focuses on the formation and development of fossil energy, development and orderly replacement of new energy, exploration and utilization of energy in deep earth and deep space, and energy development strategy and planning. The proposal of energy science is of great significance for improving the discipline system, promoting energy development, clarifying the development direction of energy transition, driving the carbon neutral geology research and constructing a habitable Earth.

Carbon dioxide is an important medium of the global carbon cycle, and has the dual properties of realizing the conversion of organic matter in the ecosystem and causing the greenhouse effect. The fixed or available carbon dioxide in the atmosphere is defined as “gray carbon”, while the carbon dioxide that cannot be fixed or used and remains in the atmosphere is called “black carbon”. Carbon neutral is the consensus of human development, but its implementation still faces many challenges in politics, resources, technology, market, and energy structure, etc. It is proposed that carbon replacement, carbon emission reduction, carbon sequestration, and carbon cycle are the four main approaches to achieve carbon neutral, among which carbon replacement is the backbone. New energy has become the leading role of the third energy conversion and will dominate carbon neutral in the future. Nowadays, solar energy, wind energy, hydropower, nuclear energy and hydrogen energy are the main forces of new energy, helping the power sector to achieve low carbon emissions. “Green hydrogen” is the reserve force of new energy, helping further reduce carbon emissions in industrial and transportation fields. Artificial carbon conversion technology is a bridge connecting new energy and fossil energy, effectively reducing the carbon emissions of fossil energy. It is predicted that the peak value of China's carbon dioxide emissions will reach 110×108 t in 2030. The study predicts that China's carbon emissions will drop to 22×108 t, 33×108 t and 44×108 t, respectively, in 2060 according to three scenarios of high, medium, and low levels. To realize carbon neutral in China, seven implementation suggestions have been put forward to build a new “three small and one large” energy structure in China and promote the realization of China's energy independence strategy.

Abstract Shale gas plays a crucial role in the national energy supply. However, fast pressure drop, production decline, and water resources pollution caused by well interference and fracture hits become more severe in multi‐layer mining shale gas fields. Such as, it is urgent to evaluate the interference of multi‐stage fracturing horizontal wells (MFHWs) between the upper and lower gas layers in Chinese Jiaoshiba shale gas field. Therefore, we put forward a comprehensive method to analyze the MFHW interference in this paper. The method contains bottom‐hole pressure response analysis (BHPRA) during neighboring well fracturing, BHPRA of well interference test, and production dynamic analysis. Our study indicates that longitudinal pressure interference exists between the Jiaoshiba upper and lower gas layers upon the apparent interference pressure response in a multi‐well test. However, MFHW interferences occur in the corresponding fracturing stages with shorter distance, and the interference strength is related to both well distance and fracturing scales. The Jiaoshiba upper gas layers can be developed to increase the gas production performance, but it is necessary to maintain a reasonable well spacing to avoid severe interference during the development.

The world's energy is in the “third major transformation period” from fossil energy to new energy, and all countries in the world have formulated energy development strategies. Through advanced deployment, the United States is about to achieve “energy independence” relying on “unconventional oil and gas revolution”. China's energy development is faced with four challenges: (1) The population base and economic development scale determine the “totally huge amount” of energy consumption; (2) the “coal rich but oil and gas insufficient” resource structure determines the “unclean” energy consuming structure; (3) the increasing dependence on imported oil and gas determines the “unsafe” energy supply; and (4) the unconventional oil and gas endowment makes it impossible to achieve energy independence by copying the American model. From the perspective of the world energy trend and the unique situation of China's energy, we put forward a “three-step” strategy for China to achieve “energy independence”: From 2020 to 2035, “energy supply security” will be addressed by “cleaning coal, stabilizing oil and gas production and vigorously developing new alternative energy”; from 2035 to 2050, the vision of “production independence” will be realized by relying on “domestic production and overseas oil and gas mining rights”; from 2050 to 2100, “intelligent energy and new energy” will help China realize “energy independence”. The two important signs of China's “energy independence” are that domestic production accounts for more than 90% of the domestic consumption and clean energy production accounts for more than 70%, and energy security realizes “independence and self-control” and “long-term security”. The strategic significance of “energy independence” is to ensure national energy security, drive the development of relevant major industries, achieve energy management reform, and implement the environmental protection goal of zero carbon emissions. The “energy independence” of China is a strategic mission, it might be fulfilled in the future with the growth of the state's power, even when the domestic energy production does not catch up with the domestic consumption. Perhaps the world's new technological revolution will exceed expectations, and China's “energy independence” dream will eventually come true. Key words: energy independence, energy revolution, intelligent energy, coal, unconventional oil and gas, new energy, energy long march

Coal-measure gas is the natural gas generated by coal, carbonaceous shale, and dark shale in coal-measure strata. It includes resources of continuous-type coalbed methane (CBM), shale gas and tight gas reservoirs, and trap-type coal-bearing gas reservoirs. Huge in resources, it is an important gas source in the natural gas industry. The formation and distribution characteristics of coal-measure gas in San Juan, Surat, West Siberia and Ordos basins are introduced in this paper. By reviewing the progress of exploration and development of coal-measure gas around the world, the coal-measure gas is confirmed as an important strategic option for gas supply. This understanding is mainly manifested in three aspects. First, globally, the Eurasian east-west coal-accumulation belt and North American north-south coal-accumulation belt are two major coal-accumulation areas in the world, and the Late Carboniferous–Permian, Jurassic and end of Late Cretaceous–Neogene are 3 main coal-accumulation periods. Second, continuous-type and trap-type are two main accumulation modes of coal-measure gas; it is proposed that the area with gas generation intensity of greater than 10×108 m3/km2 is essential for the formation of large coal-measure gas field, and the CBM generated by medium- to high-rank coal is usually enriched in syncline, while CBM generated by low-rank coal is likely to accumulate when the source rock and caprock are in good configuration. Third, it is predicted that coal-measure gas around the world has huge remaining resources, coal-measure gas outside source is concentrated in Central Asia-Russia, the United States, Canada and other countries/regions, while CBM inside source is largely concentrated in 12 countries. The production of coal-measure gas in China is expected to exceed 1000×108 m3 by 2030, including (500–550)×108 m3 conventional coal-measure gas, (400–450)×108 m3 coal-measure tight gas, and (150–200)×108 m3 CBM. Key words: coal-measure gas (CMG), coalbed methane (CBM), tight gas, continuous-type, trap-type, gas generation intensity, resource potential, coal-accumulation period, coal-accumulation area

The Kuche Depression is considered as the most important gas resource potential and gas exploring area with great gas resource potential and prospect in the Tarim Basin. Based on geochemical experimental analyses and comprehensive geological studies, the general geochemical characteristics of molecular and isotope compositions of rare gases as well as hydrocarbon gases and nonhydrocarbon gases are comparatively studied in the Kuche and Southwestern Depressions. Then, their genetic types are separately identified and gas originations are comprehensively discussed. The main results are as follows. (1) Gas fields in the Kuche Depression have a higher methane abundance, accompanied with low N2 and CO2 abundances, but the Akemomu gas field in the Southwestern Depression has a relatively lower average methane abundance, accompanied with high average N2 and CO2 abundances. The helium abundance of natural gases in gas fields from the Kuche Depression general has 1 order of magnitude higher than the air value. Comparatively, it has more than 2 orders of magnitude higher than the atmospheric value in the Akemomu gas field from the Southwestern Depression. The neon, argon, krypton, and xenon abundances in both Kuche and Southwestern Depressions are lower than the corresponding air values. (2) Natural gases from gas fields in the Kuche Depression and the Southwestern Depressions are generally typical coal-formed gases. The rare gases in the Kuche Depression have typical crustal genesis, mainly deriving from the radioactive decay of elements in the crust, while in the Akemomu gas field from the Southwestern Depression, the rare gases have main crustal genesis with a proportion of 92.5%, probably accompanied with a little mantled genetic contribution. (3) Natural gases in the Kuche Depression are generally derived from coal measure source rocks of Jurassic and Triassic, which principally originated from Jurassic in strata period and coals in source rock types. The Jurassic source rocks account for 55%-75% and the Triassic source rocks account for 25%-45% approximately, while coals occupy 68% and mudstones occupy 32% separately. Natural gases from the Akemomu gas field in the Southwestern Depression mainly originated from humic mudstones of marine and continental transitional source rocks of Carboniferous to Permian.

Liquid-rich hydrocarbons in shale strata include two kinds of resources, i.e. tight oil and shale oil. Based on the exploration and research progress of liquid-rich hydrocarbons in shale at home and abroad, their formation condition, accumulation mechanism, classification, and differences between lacustrine and marine shale systems are examined, and “sweet areas” are evaluated further. Analysis on the geological characteristics of the liquid-rich hydrocarbons in the shale strata in North America and China shows the liquid-rich hydrocarbons have two basic features: large-scale continuous distribution and no stable industrial production. The massive accumulation of the liquid-rich hydrocarbons needs four fundamental formation conditions: stable tectonic background, widespread high quality source rocks, large-scale tight reservoirs with massive reservoir space, and co-existence of source and reservoir. The study reveals the formation mechanisms of the liquid-rich hydrocarbons: source-reservoir coupling and porosity decrease during the diagenetic tightness; and identifies 24 kinds in 6 categories of the liquid-rich hydrocarbons. It is concluded that the geological conditions of the lacustrine shales in China are characterized by lower thermal gradient and stronger heterogeneity than those of North America, so large scale “sweet areas” have to be picked out to push up industrial production steadily. “Sweet areas” evaluation should consider the three aspects of geology, engineering and economics comprehensively, and the maturity of source rocks is first and foremost factor controlling the “sweet area” distribution. In China, prospective shale areas should meet the following conditions: the Ro between 0.8% and 1.3%, TOC higher than 2%, laminated shales or tight porous reservoirs, higher porosity (more than 8% for tight oil, and more than 3% for shale oil), higher content of brittle minerals (more than 70% for tight oil, and more than 40% for shale oil), oil saturation of 50%−90%, lower crude oil viscosity or higher formation pressure, and rich natural fractures. Liquid-rich hydrocarbons in shale strata are huge in resource scale, so deepening the geological understanding on the formation and distribution of liquid-rich hydrocarbons in marine and lacustrine shales constantly is of great significance for exploration and development of this important field. Key words: tight oil, shale oil, sweet area evaluation, unconventional oil and gas, fine grain sediment, tight reservoir

The Junggar Basin is located on the southwestern margin of the Central Asian Orogenic Belt (CAOB). Whether the Late Permian-Early Triassic tectonic inversion there recorded the final closure of the North Tianshan Ocean or postaccretionary intracontinental deformation remains controversial. Linking the structural style and provenance analysis of the western and northern margins of the Junggar Basin can provide a better understanding of this tectonic event and its geodynamic mechanisms. Seismic reflection profiles show that Early Permian syn-rift half-grabens were followed by the Middle Permian thermal sag, which is characterized by regional onlap and the migration of the depocentre to the centre of the basin. Together with the published isopach and palaeogeography maps in the western margin of the Junggar Basin, the seismic profiles demonstrate that the reactivation of the Ke-Bai and Wu-Xia dextral transpressive fault zones between the West Junggar terrane and the Mahu sag controlled the tilting and deformation of pre-Permian strata and the distribution of Late Permian-Early Triassic fan deltas. The reported igneous and sedimentological evidence indicates that the southern margin of the Junggar Basin was a rift basin controlled by transtensional strike-slip faults in the Early Permian, and also was followed by a Middle Permian thermal sag. Quantitative provenance analysis using detrital zircon geochronology and the DZmix program shows that the West Junggar terrane and Tianshan orogenic belts experienced varied uplift, indicative of a transition from the Middle Permian thermal sag peneplanation to the Late Permian-Early Triassic tectonic inversion involving reactivation of Early Permian normal faults. This intracontinental deformation event in the Junggar Basin was taken up by block counterclockwise rotation during the final amalgamation of the Pangea, which may be the long-range effect of the final closure of Paleo-Asia Ocean in the eastern part of the CAOB. [ABSTRACT FROM AUTHOR]