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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.

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.

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.

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

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