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Helium is a globally scarce strategic resource that is relevant to national economies and the development of high-tech industries, and China primarily depends on imported helium for its industrial applications. Therefore, there is an urgent demand for clarifying helium formation and enrichment patterns, searching for helium-rich fields, and realizing China's helium resource inventory and development potential. This article analyzes the reservoir characteristics and accumulation conditions of typical helium-rich fields in China, and clarifying the origin and source of helium as well as the main controlling factors of helium enrichment. It was recognized that helium in natural gas in China mainly comes from crustal sources. Relatively shallow buried ancient U--Th-rich granite basement or intrusion, large and stable ancient uplift or submarine formed in the early period, good overburden of huge thick paste-salt rock or mudstone cover, and channels connecting the basement and reservoir, were the main controlling factors of helium enrichment. Four types of helium-rich gas reservoirs, namely helium-rich conventional gas, helium-rich shale gas, helium-rich non-hydrocarbon gas, and helium-rich water-soluble gas, have been modeled and predicted to be helium-rich favorable exploration areas. Based on this analysis, the prospect of helium resource development in China has been analyzed. It was proposed that the exploration of helium-rich fields and the comprehensive development and utilization of medium- and low-abundance helium resources are important ways to increase the domestic helium production in China in the future. [ABSTRACT FROM AUTHOR]

To address the global warming issue, China is prioritizing the development of clean energy sources such as wind and solar power under its "dual carbon target". However, the expansion of these resources is constrained by their intermittency and the spatial and temporal distribution of wind and solar energy. This paper systematically reviews the evolution of wind and solar energy reserves, their development potential, and their current status in China from a geographical perspective. In conjunction with existing research, this paper anticipates future exploration in the realm of wind–solar complementary development or multi-energy complementary development, viewed through the lens of resource quantity. The anticipated findings are intended to furnish a theoretical foundation for further studies on the development and utilization of wind and solar energy resources within China. [ABSTRACT FROM AUTHOR]

The China Geological Survey successfully completed the second trial of natural gas hydrate (NGH) production in 2020, and the daily gas production and total gas production were greater than those in the first trial, but the evaluation of NGH resources in the South China Sea (SCS) is still in the evaluation stage, specifically for the gas content. In 2021, some scholars used different methods to more accurately evaluate NGHs in the SCS to aid in NGH exploration and evaluation in the SCS; some of them analysed the main factors controlling NGH resources, added several factors to the volume method for optimization, studied the sensitivity of the evaluation of resources to each of the main controlling factors (NGH stability zone area, NGH area coefficient, NGH stability zone thickness, NGH thickness coefficient, NGH reservoir porosity, NGH reservoir saturation, NGH volumetric ratio, NGH resource ratio coefficient and NGH recovery coefficient) and found that the effective thickness coefficient, effective thickness and effective area coefficient are the most sensitive; these values are 23.15%, 15.66%, 13.98%, and 13.95%, respectively, while the other values are 0%, 15.66%, 8.42%, 8.41%, 2.50%, and 13.92%; taking into account the influence of the main controlling factors, the range of the water resource potential evaluation results in the SCS is 2.4 × 107 m3–5.9 × 1014 m3, the modal value is 7.25 × 1011 m3, and the confidence level of the modal ±25% interval is 77.8%; these values provide a higher evaluation accuracy and higher resource level, which is consistent with the current results of NGH research in the SCS. Although the development of NGHs in the SCS is progressing rapidly, basic exploration is relatively scarce, and the number of samples of effective thickness obtained through dozens of exploratory wells is too few. It is recommended that China carry out more exploration and research projects in the Shenhu area and the entire SCS to obtain more accurate thickness data. [ABSTRACT FROM AUTHOR]

China's helium resource is highly dependent on overseas imports. Organic-rich and U/Th-rich shale reservoirs generally contain helium, and although the helium content is low, the total reserve is large. Therefore, the effective development and utilisation of shale-type helium resources is a realistic way to improve the security of helium resources in China. In this study, the generation mechanism, helium source and content, migration modes and pathways, controlling factors of enrichment, distribution pattern, and resource potential of the helium were analysed, using the Wufeng-Longmaxi shale in the Sichuan Basin and its periphery. Furthermore, countermeasures were proposed for shale-type helium exploration and development. The results show that the Wufeng-Longmaxi shale has a high content of U and Th and a good ability to generate helium. The helium is generated by a typical crustal source of helium and is characterised by self-generation, self-storage, and wide distribution. The helium resource potential is a product of its content and the resources of the associated natural gas. The continuous supply of helium and effective preservation are the main geological factors that control the enrichment of shale-type helium. The preliminary evaluation results show that the reserves of helium in proven shale gas reserves are 10.8×108 m3 in the Sichuan Basin and its periphery, where the extra-large helium fields are likely to be discovered. Additionally, 0.0912×108 m3 of helium was produced, along with the annual production of shale gas. To avoid the waste of helium and to improve the self-supply ability, it is suggested that research on the resource potential, enrichment mechanism, and distribution pattern of shale-type helium should be carried out as soon as possible, and helium extraction techniques for helium-bearing natural gas should be studied. [ABSTRACT FROM AUTHOR]

Many sets of Paleozoic marine organic-rich shale strata have developed in South China. However, the exploration and development results of these shale formations are quite different. Based on the data of core experiment analysis, drilling, fracturing test of typical wells, the reservoir differences and controlling factors of four sets of typical marine organic-rich shale in southern China are investigated. The four sets of shale have obvious differences in reservoir characteristics. Ordovician–Silurian shale mainly develops siliceous shale, mixed shale and argillaceous shale, with large pore diameter, high porosity, moderate thermal maturity, large pore volume and specific surface area. Cambrian shale mainly develops siliceous shale and mixed shale, with small pore diameter, low porosity, high thermal maturity and smaller pore volume and specific surface area than Ordovician–Silurian shale. Devonian–Carboniferous shale has similar mineral composition to Ordovician–Silurian shale, with small pore diameter, low porosity, moderate thermal maturity and similar pore volume and specific surface area to that of Cambrian shale. Permian shale has very complex mineral composition, with large pore diameter, low to medium thermal maturity and small specific surface area. Mineral composition, thermal maturity and tectonic preservation conditions are the main factors controlling shale reservoir development. Siliceous minerals in Cambrian shale and Ordovician–Silurian shale are mainly of biological origin, which make the support capacity better than Devonian–Carboniferous shale and Permian shale (siliceous minerals are mainly of terrigenous origin and biological origin). Thermal maturity of Ordovician–Silurian shale and Devonian–Carboniferous shale is moderate, with a large number of organic pores developed. Thermal maturity of Cambrian shale and Permian shale is respectively too high and too low, the development of organic pores is significantly weaker than the two sets of shale above. There are obvious differences in tectonic preservation conditions inside and outside the Sichuan Basin. Shale reservoirs inside the Sichuan Basin are characterized by overpressure due to stable tectonic activities, while shale reservoirs outside the Sichuan Basin are generally normal–pressure. Four sets of marine shale in South China all have certain resource potentials, but the exploration and development of shale gas is still constrained by complicated geological conditions, single economic shale formation, high exploration and development costs and other aspects. It is necessary for further research on shale gas accumulation theory, exploration and development technology and related policies to promote the development of China's shale gas industry. [ABSTRACT FROM AUTHOR]

In response to the environmental call for energy conservation and emission reduction, the development and utilization of shallow geothermal energy (SGE) buried pipe ground source heat pumps (GSHP) in the urban area of Linqu County has been studied. Based on geological data and water quality analysis data, ground temperature monitoring test and field thermal response test research results, using the analytic hierarchy process, the suitability of buried GSHP in the study area is computed by division, heat capacity calculation and resource potential evaluation. The results show that the development and utilization of GSHP in the study area are mainly in the moderately suitable area. The heat capacity within 120 m depth is 3.52 × 1013 kJ/°C, and the heat capacity of 200 m shallow geothermal energy is 5.84 × 1013 kJ/°C. Considering the land use coefficient, the total available heat transfer power of the buried pipe ground source heat pump is 2.56 × 106 kW. The heat transfer power in summer is greater than the heat transfer power in winter. The resource potential of buried pipe ground source heat pump is mainly in the medium potential area, and the development potential is finer in winter than in summer. Generally, the development and utilization of shallow geothermal energy in the urban area of Linqu County have broad pros. [ABSTRACT FROM AUTHOR]

With the rapid depletion of mineral resources, deep prospecting is becoming a frontier field in international geological exploration. The prediction of deep mineral resources is the premise and foundation of deep prospecting. However, conventional metallogenic predictive methods, which are mainly based on surface geophysical, geochemical, and remote sensing data and geological information, are no longer suitable for deep metallogenic prediction due to the large burial depth of deep-seated deposits. Consequently, 3D metallogenic prediction becomes a critical method for delineating deep prospecting target areas. As a world-class giant gold metallogenic province, the Jiaodong Peninsula is at the forefront in China in terms of deep prospecting achievements and exploration depth. Therefore, it has unique conditions for 3D metallogenic prediction and plays an important exemplary role in promoting the development of global deep prospecting. This study briefly introduced the method, bases, and results of the 3D metallogenic prediction in the northwest Jiaodong Peninsula and then established 3D geological models of gold concentration areas in the northwest Jiaodong Peninsula using drilling combined with geophysics. Since gold deposits in the northwest Jiaodong Peninsula are often controlled by faulting in the 3D space, this study proposed a method for predicting deep prospecting target areas based on a stepped metallogenic model and a method for predicting the deep resource potential of gold deposits based on the shallow resources of ore-controlling faults. Multiple characteristic variables were extracted from the 3D geological models of the gold concentration areas, including the buffer zone and dip angle of faults, the changing rate of fault dip angle, and the equidistant distribution of orebodies. Using these characteristic variables, five deep prospecting target areas in the Jiaojia and Sanshandao faults were predicted. Moreover, based on the proven gold resources at an elevation of −2000 m and above, the total gold resources of the Sanshandao, Jiaojia, and Zhaoping ore-controlling faults at an elevation of −5000–−2000 m were predicted to be approximately 3377–6490 t of Au. Therefore, it is believed that the total gold resources in the Jiaodong Peninsula are expected to exceed 10,000 t. These new predicted results suggest that the northwest Jiaodong Peninsula has huge potential for the resources of deep gold deposits, laying the foundation for further deep prospecting. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anomalously high-Co (>30000 ppm) pyrite occurs in the Jiaodong gold province. • Mafic dike provided the primary enrichment of Co. • High-Co pyrite formed through coupled dissolution-reprecipitation reaction. • Considerable Co resource could be formed in the hydrothermal goldfields. Traditionally, gold deposits in the Jiaodong gold province of China have been regarded as gold-only deposits lacking economic base metals. However, recent studies found some cobalt (Co) enrichment in those deposits. The mechanisms of this Co enrichment remain poorly understood. In this study, we identified a type of pyrite highly enriched in Co (concentrations up to 32800 ppm) at the Linglong gold deposit, Jiaodong gold province. The pyrite was collected from a hydrothermally altered mafic dike contacting with gold ore veins. To decipher the enrichment mechanisms of Co, in-situ textural, elemental and sulfur isotopic analyses were conducted on the pyrite. The pyrite typically exhibits core-mantle-rim textures. The cores (Py-m 1) have high Co concentrations (up to 5950 ppm) with homogeneous texture and elemental distribution, which could be the primary pyrite formed by pyritization of the mafic dike. The mantles (Py-m 2) have the highest Co concentrations (up to 32800 ppm) and contain abundant mineral inclusions (chalcopyrite, galena, and sphalerite) and pores, showing the formation through coupled dissolution-reprecipitation (CDR) reactions. The rims (Py-m 3) have low concentrations of Co (0.14–559 ppm) and show cubic shapes, forming directly from hydrothermal fluids. The δ34S values increase from the cores (4.2 ‰ to 9.1 ‰, mean of 8.0 ‰) to the mantles (8.9 ‰ to 11.9 ‰), but vary between the above two in the rims (4.2 ‰ to 12.2 ‰, mean of 9.0 ‰). The sulfur isotopic compositions of the Py-m are similar to those of pyrite (4.8 ‰ to 9.5 ‰) from the neighboring auriferous quartz-sulfide veins at Linglong in previous study. Combined with the geological and textural features, it is inferred that hydrothermal fluids during gold mineralization extracted abundant Co from the mafic dikes, leading to the primary enrichment of Co in the Py-m 1. The Py-m 1 was dissolved and re-precipitated during subsequent hydrothermal activities, forming Py-m 2 with enhanced re-enrichment of Co. Basically, the Co-rich mafic dike provided the initial enrichment of Co while the gold-bearing hydrothermal fluids contributed to concentrate Co further. Considering the widespread mafic rocks and extensive hydrothermal activities during gold mineralization throughout the Jiaodong gold province, there might be a considerable Co resource formed through the above processes. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Tonghua Basin in Northeast China potentially contains shale oil and gas resources, but the exploration and development of these resources has been limited. The Sankeyushu depression represents the sedimentary center of the Tonghua Basin, and a large thickness of shale, the Hengtongshan Formation, was deposited in this depression. Exploratory engineering discoveries in recent years have confirmed that the Hengtongshan Formation has the potential to produce oil and gas. A series of methods, including inorganic and organic geochemistry and organic petrology, have been used to study the source material, organic matter maturity, depositional environment and oil-generating potential of the Hengtongshan Formation. Investigation of drill core samples has revealed that the Hengtongshan Formation in the Sankeyushu depression is mainly composed of black shale, with a small amount of plant fossils and thin volcanic rocks, and the content of brittle minerals (quartz + carbonate minerals) is high. The provenance of organic matter in the source rocks in the Hengtongshan Formation is a mixture of aquatic organisms (algae and bacteria) and higher plants, and there may be some marine organic components present in some strata.The organic matter was deposited and preserved in a saline reducing environment. Volcanism may have promoted the formation of a reducing environment by stratification of the lake bottom water, and the lake may have experienced a short-term marine ingression with the increase in the salinity. The maturity of the organic matter in all the source rocks in the Hengtongshan Formation is relatively high, and hydrocarbons have been generated. Some source rocks may have been affected by volcanism, and the organic matter in these rocks is overmature. In terms of the shale oil resource potential, the second member of the Hengtongshan Formation is obviously superior to the other members, with an average total organic carbon (TOC) of 1.37% and an average hydrogen index (HI) of 560.93 mg HC/g TOC. Most of the samples can be classified as good to very good source rocks with good resource potential. The second member can be regarded as a potential production stratum. According to the results of geochemical analysis and observations of shale oil and natural gas during drilling, it is predicted that the shale oil is present in the form of a self-sourced reservoir, but the migration range of natural gas is likely relatively large. [ABSTRACT FROM AUTHOR]

The Sichuan Basin is rich in shale oil and gas resources, with favorable geological conditions that the other shale reservoirs in China cannot match. Thus, the basin is an ideal option for fully "exploring petroleum inside source kitchen" with respect to onshore shale oil and gas in China. This paper analyzes the characteristics of shale oil and gas resources in the United States and China, and points out that maturity plays an important role in controlling shale oil and gas composition. US shale oil and gas exhibit high proportions of light hydrocarbon and wet gas, whereas Chinese marine and transitional shale gas is mainly dry gas and continental shale oil is generally heavy. A comprehensive geological study of shale oil and gas in the Sichuan Basin reveals findings with respect to the following three aspects. First, there are multiple sets of organic-rich shale reservoirs of three types in the basin, such as the Cambrian Qiongzhusi Formation and Ordovician Wufeng Formation-Silurian Longmaxi Formation marine shale, Permian Longtan Formation transitional shale, Triassic Xujiahe Formation lake-swamp shale, and Jurassic lacustrine shale. Marine shale gas enrichment is mainly controlled by four elements: Deep-water shelf facies, moderate thermal evolution, calcium-rich and silicon-rich rock association, and closed roof/floor. Second, the "sweet section" is generally characterized by high total organic carbon, high gas content, large porosity, high brittle minerals content, high formation pressure, and the presence of lamellation/bedding and natural microfractures. Moreover, the "sweet area" is generally characterized by very thick organic-rich shale, moderate thermal evolution, good preservation conditions, and shallow burial depth, which are exemplified by the shale oil and gas in the Wufeng-Longmaxi Formation, Longtan Formation, and Daanzhai Member of the Ziliujing Formation. Third, the marine, transitional, and continental shale oil and gas resources in the Sichuan Basin account for 50%, 25%, and 30% of the respective types of shale oil and gas geological resources in China, with great potential to become the cradle of the shale oil and gas industrial revolution in China. Following the "Conventional Daqing-Oil" (i.e., the Daqing oilfield in the Songliao Basin) and the "Western Daqing-Oil & Gas" (i.e., the Changqing oilfield in the Ordos Basin), the Southwest oil and gas field in the Sichuan Basin is expected to be built into a "Sichuan-Chongqing Daqing-Gas" in China. [ABSTRACT FROM AUTHOR]

Crop straw—a carbon-neutral bio-based resource—is gaining attention because of its scalable and sustainable conversion and utilization modes amid the coordinated pollution control and carbon reduction efforts. Building on prior research with limited scope, this study introduces a multidimensional evaluation framework for spatial suitability encompassing the entire chain of conversion and utilization of crop straw resources. The framework intertwines the spatial heterogeneity and multiple conversion and utilization modes of crop straw resources, transcending the limitations of a single focus by evaluating three major modes simultaneously. In China, the spatial distribution characteristics and potential of crop straw resources at the provincial level have stabilized over time. Crop straw resources are concentrated in the provinces of North China, Northeast China, and the Middle-lower Yangtze River agricultural region, where the proportion of the flat cultivated land area is higher than 78% of the total area, and the spatial distribution is wide and concentrated. Their annual collectable potential generally exceeds 50 Mt. Spatial suitability evaluation reveals that twelve provinces, including Beijing, are suitable for promoting fertilizer utilization, eight provinces, such as Inner Mongolia, are suitable for promoting feed utilization, and ten provinces, such as Henan, are suitable for promoting energy utilization. Overall, this study informs policymakers on optimization strategies for the high-quality and efficient conversion and utilization of crop straw resources. • A multi-dimensional evaluation approach for spatial suitability is presented. • Multiple modes are included in evaluation scope. • A mapping relationship between provinces and modes is formed. • The overall distribution characteristics and resource potential remain stable over time, with provinces clustered into three clusters. • Directions for future policy optimization are offered. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Ordos Basin is the largest and most important intracontinental sedimentary depression in China, and a significant amount of crude oil resources has developed within this Mesozoic formation. High-grade organic-rich shale is prevalent in the large-scale areas of the Chang 7 sedimentary stage and provides essential hydrocarbon resources for abundant oil enrichment in the Mesozoic. This research investigated the geochemical characteristics of Chang 7 shale using core samples and well logs and via laboratory tests. In addition, the microscopic components of the shale organic matter (OM), biological marker compounds, carbon isotopes, enrichment grade of trace elements, and elemental ratio were analysed systematically. Moreover, the aspects related to the shale OM source, sedimentary environment and resource potential were evaluated. Our results revealed that spherical alginate and calcium spherical alginate were predominant in the micropetrological components of the shale. Many biomarkers, including n -alkanes, steranes and terpanes, were detected in the gas chromatography – mass spectrometry spectra. An analysis of n -alkanes, regular sterane shapes (C21−/C22− and C26+C27/C28+C29), odd–even predominance index (OEP) and carbon preference index (CPI) values and carbon isotope distributions showed that OM was produced from aquatic organisms. The indicators of trace elements, such as Sr/Ba and V/V+Ni, combined with the biomarker compound in Pr/Ph and the gammacerane index showed the presence of a semi-deep – deep lake environment containing fresh–brackish water. In addition, the hydrocarbon conversion rate index and shale rock pyrolysis parameters revealed that Chang 7 has a high hydrocarbon generation ability and hydrocarbon expulsion efficiency. [ABSTRACT FROM AUTHOR]

Abstract Shale oil refers to oil stored in organic-rich shale. It is an important part of unconventional oil and provides a large amount of resources. Based on the systematic study of the geological characteristics of shale oil in China's major continental basins, the geological connotation of the "sweet area (section)" in shale oil is proposed in this paper, and it refers to areas (sections) that can be preferentially explored and developed in oil-bearing shale formations under current economic and technical conditions. The formation conditions and distribution characteristics of continental shale oil in China are analyzed with a focus on the geological properties of the Triassic Yanchang Formation in the Ordos Basin, the Cretaceous Qingshankou Formation in the Songliao Basin and the Permian Lucaogou Formation of the Jimusar Sag in the Junggar Basin. It is found that the "sweet areas" of shale oil with medium-high maturation are mainly located in thick shales with a Ro greater than 0.9%, and the "sweet sections" are mainly located in the middle and lower parts of the shale formation. The geological resources of continental shale oil in the major continental basins in China are estimated to be approximately 3700 × 108 tons. The in situ conversion process (ICP) may be a key technology for the effective development of medium-to low-mature shale oil. The scale, maximum burial depth and present depth of the organic-rich shale are proposed as the three key parameters for the optimization of pilot sites by taking the Triassic Yanchang Formation in the Ordos Basin as an example. Using ICP, it is expected that the recoverable resources of China's continental shale oil will be approximately (400–500) × 108 tons. The terminology of "man-made reservoir" is proposed in this paper. In an "man-made reservoir", the overall industrial output of the "sweet areas (sections)" is formed by artificial intervention and the construction of an underground fracture network system with "man-made permeability". Continental shale oil may be another revolutionary source of unconventional oil and is expected to be first successfully produced in China. Highlights • The "sweet areas(sections)" of continental shale oil with medium-high maturation are illustrated with examples and the resources are assessed. • The formation conditions and distribution characteristics of continental shale oil in China are analyzed. • Some important concepts are proposed, including "exploring oil into source kitchen", "source rock oil", "man-made oil reservoir", etc. [ABSTRACT FROM AUTHOR]

Numerous buried ferromanganese (Fe-Mn) crusts covered by surface sediments, such as foraminifera ooze, were found on the platforms of certain guyots in the Western Pacific Ocean. To examine the origin of these shallow-buried (<100 cm below the seafloor) Fe-Mn crusts and evaluate their resource potential, we conducted mineralogical and geochemical studies on seven drill cores from the Weijia Guyot(Ita Mai Tai Guyot), which is in the Co-rich Fe-Mn crust contract area of the China Ocean Mineral Resources Research and Development Association (COMRA).The buried Fe-Mn crusts exhibit multilayer structures and are composed of disordered vernadite, similar to the exposed Fe-Mn crusts. Moreover, they show comparable contents of major metallogenic elements (e.g., Mn, Cu, Co, and Ni) and platinum group elements when compared to exposed Fe-Mn crusts. However, they have much higher contents of rare earth elements (REEs) than those of exposed Fe-Mn crusts, indicating a comparable resource potential. The high P contents and collophanite observed in the petrographic microscope indicate that an evident phosphatization event occurred. Based on the tectonic evolution and sedimentation rate, we infer that the phosphatization event mainly took place before the crusts were buried. The phosphatization of shallow-buried Fe-Mn crusts results in an enrichment of REEs and their fractions. This process can also modify the sedimentary environment for Ce precipitation, which may, in turn, alter the diagenetic microenvironment of the shallow-buried Fe-Mn crusts. The mineralogical and geochemical results reveal that burial doesn't cause a significant difference between shallow-buried and exposed Fe-Mn crusts from Weijia Guyot, and they are still of hydrogenetic origin. The findings and research on shallow-buried Fe-Mn crusts indicate that they have comparable resource potentials with exposed Fe-Mn crusts. These results will influence future decisions related to the exploration, exploitation, and utilization of Co-rich Fe-Mn crusts in the contract area of COMRA. Furthermore, it could provide valuable insights for other contractors investigating the platform. [Display omitted] • The shallow buried Fe-Mn crusts were found to be widely distributed on the Weijia Guyot. • They have comparable base and PGEs metal concentrations to the exposed crust. • They show rare earth element enrichment as a result of phosphatization. • Their resource potential will influence the decision on future exploration. [ABSTRACT FROM AUTHOR]

The Triassic formation is a possible new giant hydrocarbon generated formation in Northwest China and Mid-Asia. Taking the Upper Triassic formation in the Sikeshu Sag in Junggar Basin as an example, based on the comprehensive analysis on the geochemical characteristics of the cores and the dark mudstone of the outcrops and reservoir formation conditions, we have evaluated the Upper Triassic source rocks by comparing with those in the Ulungu Depression, and reached the following findings. Firstly, the Upper Triassic formation is mainly composed of dark mudstone and sandy mudstone deposits, and the hydrocarbon source rock is mainly distributed in the middle and upper parts with a thickness range of 100–150 m and area of 3500 km 2 . Secondly, the source rock, moderate in organic matter abundance (with TOC range of 1%–3%), has the material basis for hydrocarbon generation. Thirdly, the organic matter has high percentage of sapropelinite, and is dominated by type II 2 . Fourthly, the degree of the thermal evolution is moderate, and the source rock with R o higher than 0.7% has a distribution area of about 1800 km 2 , providing the conditions of massive hydrocarbon generation. Fifthly, the source rock has great burial depth and wide distribution; the source rock with a R o of higher than 0.7% and thickness of more than 100 m has an area of around 1400 km 2 , implying huge resource potential. Sixthly, the next step exploration should focus on highly mature hydrocarbon generation central area in the Upper Triassic - Lower Jurassic in the east of the sag to search for and confirm favorable traps. The research findings have important reference value for promoting the resource status of, deepening the understanding of reservoir formation, and clarifying the exploration direction in the Sikeshu Sag and other periphery Mid-Asia areas. [ABSTRACT FROM AUTHOR]

Although tight oil has great resource potential, studies of oil charging mechanisms in tight reservoirs are relatively few. Researchers have found that a force balance exists during oil charging, but quantitative analyses of conditions critical for tight oil charging are sparse. This study developed a formula to identify effective source rocks using oil expulsion intensity as the discrimination parameter based on quantitative expression of hydrocarbon-generation overpressure and force-balance conditions. Using this formula, critical oil expulsion intensity under conditions at various burial depths can be obtained. This method was applied in the tight reservoirs of the Jimusar Sag, Junggar Basin, China. The calculated critical oil expulsion intensity range was between 122.61 × 104t/km2and 620.01 × 104t/km2. The distribution range of effective oil source rocks and total expelled oil can be determined on the basis of critical oil expulsion intensity at different burial depths. This method provides a new approach to predict favourable tight oil-bearing regions. [ABSTRACT FROM AUTHOR]

As one of the most important renewable and sustainable energy sources, the forest biomass energy resource has always been the focus of attention of scholars and policy makers. However, its potential is still uncertain in China, especially with respect to its spatial distribution. In this paper, the quantity and distribution of Chinese forest biomass energy resources are explored based mainly on forestry statistics data rather than forest resource inventory data used by most previous studies. The results show that the forest biomass energy resource in China was 169 million tons in 2010, of which wood felling and bucking residue (WFBR),wood processing residue (WPR), bamboo processing residue, fuel wood and firewood used by farmers accounted for 38%, 37%, 6%, 4% and 15%, respectively. The highest resource was located in East China, accounting for nearly 39.0% of the national amount, followed by the Southwest and South China regions, which accounted for 17.4% and 16.3%, respectively. At the provincial scale, Shandong has the highest distribution, accounting for 11.9% of total resources, followed by Guangxi and Fujian accounting for 10.3% and 10.2%, respectively. The actual wood-processing residue (AWPR) estimated from the actual production of different wood products (considering the wood transferred between regions) showed apparent differences from the local wood processing residue (LWPR), which assumes that no wood has been transferredbetween regions. Due to the large contribution of WPR to total forestry bioenergy resources, the estimation of AWPR will provide a more accurate evaluation of the total amount and the spatial distribution of forest biomass energy resources in China. [ABSTRACT FROM AUTHOR]

Abstract: The features and exploration potential of the Permian tight oil in the Junggar Basin were analyzed and evaluated using outcrop, core and geochemical data etc. The Junggar Basin in the Early-Mid Permian is a saline lacustrine basin after the residual sea is closed, a set of hybrid sedimentation of deep-lake dark mudstone and dolomitic rock is developed, and the high-quality mudstone source rocks and the dolomite mudstone are alternated. High quality source rocks in mature stage are next to tight dolomitic rock reservoirs closely and provide good conditions for tight oil accumulation of proximal source type. Tight oil reservoirs are mainly distributed in the centre and slope region of the lake basin, and two types sweetspots of “dissolved pore” and “fracture-pore” exist locally. The enrichment of tight oil is controlled by the distribution of effective source rocks and dolomitic rocks, and the tight oil occurs in the entire strata vertically and spreads across large continuous areas horizontally. The Junggar Basin has four Permian tight oil distribution areas, Fencheng Formation in the Mahu sag, Lucaogou Formation in the Jimusaer sag, Pidiquan Formation in the Shazhang-Shishugou sag, and Lucaogou Formation in the Bogeda piedmont. A number of wells obtained oil flow in these areas, suggesting great resource potential and favorable targets for future exploration. [Copyright &y& Elsevier]

Abstract: Based on the formation mechanism of water-soluble gas, combined with the geological conditions of the Palaeogene Huizhou Sag, the resource potential and utilization of water-soluble gas in the Palaeogene source rock in the Huizhou Sag are analyzed quantitatively using grid calculation method. The Palaeogene Wenchang and Enping formations of the Huizhou Sag are major source rocks that generate significant quantities of gas and the sandstone reservoirs are weakly overpressured to overpressured on the whole. Calculated according to the thickness, sandstone content, porosity, water saturation, strata pressure, temperature, and mineralization of the Wenchang and Enping Formations, the resource volume of water-soluble gas is about 1 791.49×108 m3 and 2 688.5×108 m3, 1.19 and 3.46 times that of the conventional gas, respectively. If the strata pressure is relieved to normal pressure, the degasification volume is 80.84×108 m3 and 97.04×108 m3. The water-soluble gas is an unconventional resource with great potential, and can provide substantial gas source for conventional pools through degasification. [Copyright &y& Elsevier]

Abstract: Based on analysis of the characteristics of unconventional hydrocarbon resources, this paper assesses the potential for unconventional hydrocarbons in China, summarizes the key technical progress in exploration and development, and discusses the prospects and developing strategies of unconventional hydrocarbons. The resources of unconventional oil and gas in China are abundant. The recoverable tight gas ranges from 8.8×1012 m3 to 12.1×1012 m3, the recoverable shale gas is from 15×1012 m3 to 25×1012 m3, the recoverable coalbed methane 10.9×1012 m3, the recoverable tight oil from 13×108 t to 14×108 t, and the recoverable shale oil 160×108 t. There is also some resource potential for oil sand. Such key techniques as the full-digital seismic exploration, low permeability and low resistivity reservoirs identification have been developed and their applications in oil and gas fields have achieved good results. Tight gas and tight oil are the most realistic resources to develop in China and the development and utilization of coalbed methane and shale gas are at a pioneer stage. In the next ten or twenty years, the production of unconventional hydrocarbon in China will increase considerably and play a major role in national hydrocarbon resources. [Copyright &y& Elsevier]

Abstract: According to the latest drilling data, the geologic survey of surrounding outcrops and the laboratory test results of rock samples, this paper studies the regional distribution, geochemical and reservoir characteristics and gas concentration of organic-rich shales to reveal the shale gas generation and potential of the Lower Cambrian Qiongzhusi Formation of the Southern Sichuan Basin. The study area features high organic content (with TOC between 0.55% and 25.7%, average of more than 2%), great net shale thickness (of 60–300 m), high brittle mineral content (over 40%), abundant micro- and nanometer-sized pores and micro-fractures, and high gas content (0.27–6.02 m3/t, average of 1.90 m3/t), which is in favor of the generation and accumulation of shale gas. The Lower Cambrian Qiongzhusi Formation is one of the most favorable strata which has frequent gas show and industrialization breakthrough during drilling, and the Weiyuan and Xunyong-Junlian areas are two most realistic and favorable targets for shale gas exploration and development. [Copyright &y& Elsevier]

The Shahejie Formation of the Bohai Bay Basin has been set as a favorable shale oil area for exploration in currently practice. However, the process was impeded by the obscurity of favorable exploration area in the shale play and resource evaluation targeted at the main research area, the Qikou Sag. In particular, there is a need for a systematic assessment of the various types of resources present. The study presented herein emphasizes on quantifying source rock generation, expulsion, and retention hydrocarbon characteristics using the advanced hydrocarbon-generation potential model (HGPM) in the first member of the Paleogene Shahejie Formation (Es 1) of the Qikou Sag. Geological and geochemical features reveal that the Es 1 source rocks are of relatively high quality with a 1200-m maximum thickness and abundant organic matter (total organic carbon (TOC) content of 2.27% on average; type I kerogen dominated; mature stage). The type of organic matter was reassessed using the progressive and reasonable dimensionless TOC and S 2 variables. The HGPM demonstrated that the expulsion threshold was R o = 0.50% and the maximum generation hydrocarbon potential (Q g), expulsion hydrocarbon potential (Q e), and retention potential (Q r) were 746.99, 231.57, and 515.42 mg HC/g TOC, respectively. The hydrocarbon generation (I g), expulsion (I e), retention (I r), and effective retention intensity (I re) all centered in the Qikou main depression at 450 × 104, 200 × 104, 300 × 104, and 230 × 104 t/km2, respectively. The predicted resource potential can be finally queued as follows: retention shale resources with 22.90 × 108 t oil equivalent, including movable shale oil and gas of 12.21 × 108 t, and conventional and tight oil or gas resources with 9.62 × 108 t oil equivalent. The most favorable exploration areas are mainly distributed in the Qikou main depression and Qibei Subsag. Quantitative and detailed evaluation provides a reasonable prediction of exploration targets and prospects and further mitigates risks and losses incurred during shale-exploration successions. • Advanced hydrocarbon generation potential model is used in the Qikou Sag, NE China. • Potential resources and favorable targes of study area are presented. • Redetermination on organic matter type and redescription on HC generation process. • Unconventional oil and gas occupy a desirable resource scale. • The resources comparisons between Qikou Sag and the adjacent Nanpu Sag. [ABSTRACT FROM AUTHOR]

China has the largest antimony (Sb) resources, products and consumption in the world, which plays an important role in the global antimony trade. Chinese Sb deposits are characterized by large resources, concentrated distributions, primary deposits dominating, and associating with numerous valuable elements and minerals. In China, most of Sb deposits are located at the edges of various geotectonic units and are constrained by plate suture zones or large deep fault belts. There are 5 Sb metallogenic belts were distinguished in this paper including the Tianshan-Xingmeng Sb ore belt, Qin-Qi-Kun Sb ore belt, Qiangtang-Sanjiang Sb ore belt, South China Sb ore belt and South Tibet Sb ore belt. Sb deposits are hosted in Mesoproterozoic to Quaternary formations, but most of them were occurred in Precambrian, Devonian and Triassic strata. The ages of mineralization of Sb deposits in China are mainly concentrated in the Indosinian, Yanshanian and Himalayan, while the large-scale mineralization is restricted within the Jurassic to Cretaceous of the Yanshanian. Antimony deposits have multiple sources of ore-forming metals and fluids, of which Precambrian basement strata may be one of the most important. The magmatic activity caused by asthenosphere upwelling may be the main evocator for driving the circulation of groundwater to extract mineralized elements. According to the results of China National Mineral Resources Potential Assessment Project (NMRP), China delineated 94 Sb prospect areas, in which, 15.43 million tons of unproven Sb metal were predicted within 2 km below the surface. Among the 5 Sb ore belts, the South China Sb Ore Belt has the largest number of deposits, identified resources and resources potential, showing strongest mineralization intensity. The Qiangtang-Sanjiang Sb Ore Belt followed, where may become the future antimony resource-base of China. [Display omitted] • The Sb deposits in China are distributed throughout five metallogenic belts. • The Sb metallogenic mainly occurred during Yanshanian in China. • Deep magmatism is the main driving force of the ore fluid circulation. • China has estimated 15.43 million tons Sb metal in 94 prospect areas. [ABSTRACT FROM AUTHOR]

In recent years, significant progress and breakthroughs have been made in the exploration of conventional and unconventional natural gas in the Lower Cambrian petroleum system in the Sichuan Basin in Central China, showing excellent exploration prospects. However, detailed evaluation of the Qiongzhusi shale, the main source rocks in the Lower Cambrian petroleum system, including their hydrocarbon generation and expulsion characteristics, is lacking, even though such evaluation is critical for understanding conventional and unconventional natural gas resource potential. To investigate the geological and geochemical characteristics of the Qiongzhusi shale, experiments including pyrolysis, total organic carbon (TOC), vitrinite reflectance (Ro), gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) were conducted. Based on modeling work and fluid inclusion analysis, the hydrocarbon generation and expulsion characteristics of the Qiongzhusi shale and their control on hydrocarbon accumulation was analyzed, and the conventional and unconventional natural gas resource potential of the Lower Cambrian petroleum system was systematically evaluated. The results indicate that the organic matter of the Qiongzhusi shale is mainly derived from bacteria and algae deposited in a saline, reducing marine environment. The shale is predominantly composed of type I kerogen with an average TOC value of 1.85 wt%, and is widely distributed in the basin with an average thickness of 212.7 m. The Qiongzhusi shale is primarily post-mature with an average vitrinite reflectance (Ro) of 2.53%. Modeling work suggests the Qiongzhusi shale reached the hydrocarbon expulsion threshold (HET) at Ro = 0.9%, and the main hydrocarbon expulsion stages are Triassic, Jurassic, and Cretaceous. The maximum hydrocarbon generation and expulsion intensities at present day are 32 × 106 t/km2 and 18 × 106 t/km2, respectively. The conventional natural gas resource potential of the Longwangmiao Formation derived from the Qiongzhusi shale is estimated to be between 9.51 × 1012 m3 and 19.03 × 1012 m3. The unconventional shale gas resource potential of the Qiongzhusi shale is predicted to be 1.4 × 1012 m3, showing significant prospects for natural gas exploration. • Geochemistry characteristics of the Qiongzhusi Formation were systemically evaluated. • Hydrocarbon generation and expulsion characteristics of the Qiongzhusi Formation were first analyzed. • Conventional and unconventional natural gas resource potentials of ancient Lower-Cambrian petroleum system were calculated. [ABSTRACT FROM AUTHOR]

• The major minerals potential have been evaluated in China. • The layout of mineral exploration is undergoing tremendous changes in China. • China has great potential of mineral resources. China is located at the convergence zone of the Paleo-Asian metallogenic domain, East Pacific margin metallogenic domain, and Tethyan metallogenic domain. Theoretically, this feature favor metallogenic conditions, which suggest an abundance of mineral resources. Today, the rapid development of urbanization and industrialization has triggered a continuously increasing demand for and a large scale consumption of mineral resources. Therefore, in order to satisfy this demand, China has furthered its evaluation of mineral resources potential to help guide future mineral explorations. Based on the innovation of geological theory, prediction and prospecting models, as well as GIS-based comprehensive assessment methods, 25 important mineral resources and key metals have been assessed in China. Herein, we evaluate the national mineral resources assessment study by combining it with metallogenic areas (belts) research. Through our analyses, we identify the potential characteristics of important mineral resources in different metallogenic areas (belts) to enhance the scientific decision-making process for the exploration and deployment of mineral resources in China. We found that the exploration and deployment of bulk minerals such as iron, manganese, and copper are continuously changing. Currently, the eastern region should be the primary focus of deep prospecting, while exploration for copper, lead, and zinc should occur in the central and western regions. [ABSTRACT FROM AUTHOR]

The Anyue giant gasfield was discovered in the Sinian-Cambrian Central Sichuan region of the Sichuan Basin in 2013, with geological reserves up to 1×1012m3, which is the first time for the exploration of natural gas paleo-reservoirs in the world. The gas source studies suggest that the Sinian natural gas is originated from the Sinian and Cambrian hydrocarbon source rocks, and the systematical study on the Sinian and Cambrian ancient source rocks has important scientific and practical significance for the global oil and gas geologic domain of the ancient stratum. Based on the drilling data and field profile observation of Sinian and Cambrian in Sichuan Basin, with adoption of the interpretation data of 28 000 km-seismic and new drilling data, combined with geochemical analysis of source rocks of 2 315 samples, this paper systematically studied the high quality hydrocarbon source rock center, where the source rocks are mainly distributed along the Mianzhu-Changning craton inner rift, with a accumulative thickness reaching 200-450m, and 50-100m for the thickness of source rocks in other areas. The hydrocarbon source rocks of the Sinian-Cambrian contributed about 56%-63% of natural gas resources of the whole basin. Systematical evaluations have been conducted to the mudstone source rocks and their distribution in the Ⅲ-section of Sinian Dengying Formation, where TOC value is ranging from 0.04% to 4.73%, with an average of 0.65%. The thickness of the source rocks in central Sichuan region is ranging from 10 to 30 m. The oldest Sinian source rocks that can form large gasfields in China were systematically studied for the first time,and the total gas production intensity of the Sinian source rocks in the great central Sichuan region is (15-28)×108m3/km2, where the gas source conditions for the formation of large gasfields are available. By using the genetic method and analogy method, the amount of natural gas resources of the Sinian-Cambrian in the basin are re-evaluated as (4.65-5.58)×1012m3, and the resources potential of natural gas is huge. The amount of natural gas resources in the central Sichuan block accounts for about 66% of the total basin resources, which is the preferred selection for current exploration. [ABSTRACT FROM AUTHOR]