Article
Green & Sustainable Science & Technology
Jing Wang, Fawang Ye, Gary G. Lash, Zhaodong Xi
Summary: This study used scanning electron microscopy to investigate the types of organic matter and pore development in shale deposits in southern China, and found that the sedimentary environment is the main factor influencing these features.
Article
Geosciences, Multidisciplinary
Tao Wang, Fenghua Tian, Ze Deng, Haiyan Hu
Summary: The microscopic pore characteristics of shale in marine strata in northern Yunnan and Guizhou were evaluated using FE-SEM, LT-N(2)GA, LP-CO(2)GA, and HPMA experiments. Fractal Frenkel-Halsey-Hill theory was used to analyze the fractal characteristics and discuss the adsorption pore characteristics of shale. The results showed that the shale samples had complex pore structures and open pore styles, with abundant micropores and mesopores. The fractal dimensions were positively correlated with the TOC and clay mineral contents and negatively correlated with the quartz content. Fractal analysis is helpful for understanding the pore structure and adsorption capacity of shale gas reservoirs.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Wenping Liu, Juan Wu, Hua Jiang, Zheng Zhou, Chao Luo, Wei Wu, Xiaojia Li, Shugen Liu, Bin Deng
Summary: This study examines the relationship and multi-stage evolution between the upper Ordovician Wufeng and lower Silurian Longmaxi formations at the Changning shale gas field in southern Sichuan basin. The research utilizes low-temperature thermochronological data and structural evolution to analyze the rapid exhumation and history of the field. The results suggest a four-stage thermal evolution and significant impact of pressure index changes on shale gas enrichment.
MARINE AND PETROLEUM GEOLOGY
(2021)
Article
Engineering, Environmental
Wenbin Jiang, Gaohui Cao, Chao Luo, Mian Lin, Lili Ji, Ji Zhou
Summary: The study investigated the relationship between the composition of Wufeng-Longmaxi Formation shale samples in Sichuan Basin and methane adsorption characteristics, establishing a composition-based methane adsorption model. Differences in clay contribution to methane adsorption for different sublayers were revealed, aiding in improving the accuracy of shale reservoir evaluation.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Geochemistry & Geophysics
Jianlin Guo, Chengye Jia, Dongbo He, Fankun Meng
Summary: The study proposed classification criteria for net pay of shale gas reservoirs in the Shunan area of the Sichuan Basin, based on the analysis of porosity, gas saturation, density of rock, brittleness index, and gas content. The application of gas content and brittleness index parameters reflects reservoir resource basis and fracability respectively. The net pay can be classified into three types based on the ranges of these two parameters, with implications for testing production and economic benefits.
Article
Chemistry, Multidisciplinary
Guoliang Xie, Weiduo Hao
Summary: This study investigated different organic matter pores in the Longmaxi Formation shales in the Sichuan Basin using optical microscope, SEM, and adsorption experiments. The results showed that pyrobitumen and quartz-rich brittle shale play significant roles in pore development, while pores in organic matter like microorganisms and algae are mainly mesopores.
Article
Geosciences, Multidisciplinary
Wei Cheng, Xiaowen Zhang, Juan Jin, Jiandong Liu, Weidong Jiang, Guangming Zhang, Shihuai Zhang, Xiaodong Ma
Summary: This paper presents an experimental investigation on the time-dependent deformation of the Longmaxi shale gas shale, revealing that the shale samples exhibit varying degrees of time-dependent deformation, and can be adequately described by a power-law function of time. The experimental results establish the relationship between the elastic Young's modulus and viscoplastic constitutive parameters, which are different from those derived from North American shales. Furthermore, the characterized viscoplasticity and stress relaxation are of vital importance for various geomechanical problems in shale reservoirs.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Lulu Xu, Saipeng Huang, Yang Wang, Xianghui Zhou, Zaoxue Liu, Yaru Wen, Yanlin Zhang, Mengdi Sun
Summary: The deposition of black shale is influenced by several factors, including organic matter input, preservation, and dilution. The individual contribution of these factors to organic matter enrichment is complex due to variations in palaeodepositional conditions. This study investigated the palaeoenvironmental conditions and organic matter enrichment mechanisms in the Wufeng-Longmaxi Formation in western Hubei. The findings reveal the presence of different mineral compositions in the Guanyinqiao Formation and variations in silica origin, warm and humid climate, and factors influencing organic matter enrichment.
MARINE AND PETROLEUM GEOLOGY
(2023)
Article
Energy & Fuels
Shengxiu Wang, Jia Wang, Yuelei Zhang, Dahua Li, Weiwei Jiao, Jinxi Wang, Zhian Lei, Zhongqiang Yu, Xiaojun Zha, Xianfeng Tan
Summary: Through organic geochemical and reservoir characteristic analysis, the features of the Wufeng-Longmaxi formation shale and reservoir characteristics were identified. The study revealed a positive correlation between TOC and quartz content, and a positive correlation between porosity and clay mineral content. Therefore, shale with high TOC content, high clay mineral content, and suitable quartz content is the most favorable interval for shale gas exploration and development.
Article
Energy & Fuels
Ping Gao, Xianming Xiao, Dongfeng Hu, Ruobing Liu, Yidong Cai, Tao Yuan, Guangming Meng
Summary: This study investigated the water content and its distribution in the different nanopores of deep and ultra-deep shales in China. The results showed that irreducible water is the dominant form of water in ultra-deep shales, primarily occurring in clay-hosted pores and parts of organic pores. It is mainly distributed in non-micropores, especially in micropores with a diameter of 0.4-0.6 nm and mesopores with a diameter of 2-10 nm. The presence of irreducible water significantly affects the specific surface area of non-micropores, which is more pronounced in organic-rich shale samples.
Article
Chemistry, Multidisciplinary
Wei He, Tao Li, Bixin Mou, Yuxue Lei, Jinhui Song, Zhicheng Liu
Summary: This study investigated the petrology and lithofacies of the shale samples from the Wufeng Formation-Member 1 of the Longmaxi Formation in the Xichang Basin. It identified nine lithofacies and determined the lithofacies that are favorable for shale gas accumulation. This study is important for the exploration and development evaluation of shale gas.
Article
Geosciences, Multidisciplinary
Tonglou Guo, Xianghao Meng, Wei Lei, Mingming Liu, Liang Huang
Summary: This study conducted systematic experimental characterization to understand the pore structures and methane sorption in deep-marine shales. The results showed that factors such as organic matter content and clay minerals affect the pore structures and sorption behaviors in deep shales. The findings also indicate that deep shales have higher micropore content from organic matter and lower macropore content from clay minerals compared to shallow shales. The total organic carbon (TOC) content is the primary controlling factor on pore structure and sorption capacity in deep shales, while the influence of clay minerals on gas sorption is less pronounced.
NATURAL RESOURCES RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Jing Wu, Chao Liang, Renchao Yang, Jun Xie
Summary: This study examines the occurrence and importance of organic matter-mineral associations (OMMA) in shale gas reservoirs in the Sichuan Basin, identifying the impact of different types of OMMA on reservoir quality. The research also identifies four important lithofacies and highlights the heterogeneous distribution of OMMA in influencing hydrocarbon generation and gas storage conditions among different lithofacies.
MARINE AND PETROLEUM GEOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Xu Yu, Cheng Zhai, Yu Jing, Shuxun Sang, Yu Wang, Klaus Regenauer-Lieb, Yong Sun
Summary: This study presents an experimental investigation into the effect of temperature on the chemical-mechanical properties of shale rocks. The results indicate that high temperatures can significantly impact the weight and mechanical strength of shale samples, as well as the chemical reaction rates associated with shale compositions. The study also demonstrates the influence of compositional changes on the mechanical properties of shale rocks.
Article
Energy & Fuels
Zhonghua Liu, Baojun Bai, Zhongpei Ding, Hai Qu, Shunpeng Zeng, Xuejuan Da
Summary: The experiments demonstrated that cleanup additive treatment decreases adsorption capacity and increases adsorption intensity. There is an intersection between the desorption efficiency curves before and after treatment. Cleanup additive helps translate adsorbed phase into free phase, improving free gas content and increasing cumulative gas production.
Article
Energy & Fuels
Jingqiang Tan, Ruining Hu, Wenbin Luo, Zhongliang Ma, Guangmang He
Summary: The pore structure evolution of immature organic-rich shale from the Paleogene Huadian Formation was studied, revealing that most oil-generating stages occur between 300 and 400 degrees Celsius. The thermal simulation samples mainly developed wedge-shaped or slit-shaped pores, with pore size distribution mainly within the bimodal distribution of 0.5-0.8 and 30-100 nm.
Article
Geochemistry & Geophysics
Xun Kang, Wenxuan Hu, Jingqiang Tan, Zhongping Li, Baoli Xiang, Jian Wang, Xiaolin Wang
Summary: This study analyzed natural gases from deep buried oxidized reservoir rocks, showing a unique trend of hydrogen and carbon isotopes in hydrocarbons. The results suggest that thermochemical oxidation of hydrocarbons induced by high-valence metal oxides can cause significant differences in hydrogen isotopic compositions and carbon isotopic enrichments in natural hydrocarbons.
Article
Energy & Fuels
Dongyu Wu, Huaidong Zhang, Shaohe Zhang, Jingqiang Tan, Pinghe Sun, Yongjiang Luo, Shuai Gao, Yanhong Xue
Summary: The study focused on the bottom-hole cleaning performance of swirling jet induced by a drill bit nozzle. Computational fluid dynamics simulations were conducted to compare swirling jet with straight jet, showing that swirling jet had poorer cleaning performance than straight jet in removing drilled cuttings.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Plant Sciences
Minghao Du, Jaak Nolvak, Jingqiang Tan, Shijia Gao, Wenhui Wang
Summary: This study presents a new analysis of melanosclerites from the Late Ordovician to earliest Silurian, identifying 12 species and plotting their palaeogeographical occurrences on an up-to-date map. The distribution pattern of these organisms shows a tendency to occur in low-latitude, warm-water regions, mainly confined within the tropics and subtropics. Comparing with Palaeozoic hydroids, both fossils overlap in palaeogeographical distribution, indicating a potential close biological affinity between the two types of organisms.
Article
Engineering, Geological
Jingqiang Tan, Bingbin Xie, Qiao Lyu, Shefa Chen, P. G. Ranjith
Summary: The effects of CO2 and CO2-based fluids imbibition on the mechanical properties of shale are investigated in this study. The results show that the mechanical properties of shale have significant variations after different imbibitions, with the largest effect observed for sub-CO2-water and Sc-CO2-water imbibitions. Pure CO2 saturation has the smallest effect on shale's mechanical properties. The statistical damage constitutive model used in this study can well describe the stress-strain relationship of shale under different soaking conditions.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Thermodynamics
Biao Shu, Yimin Wang, Runjun Zhu, Leilei Liu, Jingqiang Tan, Jeffrey Dick
Summary: This study investigates the impact of temperature and confining pressure on the heat transfer coefficient and energy extraction efficiency in deep geothermal energy. The experiments show that increasing rock temperature enhances the heat transfer coefficient and energy extraction rate, while increasing confining pressure decreases them. Additionally, the energy consumption of the pump used for fluid flow is not significantly affected by temperature and confining pressure.
APPLIED THERMAL ENGINEERING
(2022)
Article
Energy & Fuels
Qiao Lyu, Jindong Shi, Jingqiang Tan, Jeffrey M. Dick, Xun Kang
Summary: This study quantitatively describes the effects of deionized water and NaCl solution on shale permeability through permeability tests. The results show that NaCl solution imbibition leads to a stronger and more complex decrease in shale permeability compared to deionized water imbibition. In addition, shale swelling and water-blocking effects increase the sensitivity of shale permeability to pore pressure.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Energy & Fuels
Jingqiang Tan, Chenger Hu, Qiao Lyu, Gan Feng, Shefa Chen
Summary: Through a series of imbibition tests, it was found that fracturing fluids with different pH values have a significant impact on the surface roughness of shale fractures, with alkaline fracturing fluid having the greatest effect. Additionally, the joint homogeneity of shale fractures also changes during the fluid-rock interaction process.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Ecology
Jeffrey M. Dick, Jingqiang Tan
Summary: By combining taxonomic abundances from 16S rRNA gene sequencing datasets with reference microbial proteomes from the NCBI RefSeq database, the carbon oxidation state of estimated community proteomes can be used as a proxy for environmental redox conditions. Analysis of multiple datasets confirms this prediction.
Article
Engineering, Geological
Qiao Lyu, Kaixi Wang, Chenger Hu, Jeffrey M. Dick, Jindong Shi, Jingqiang Tan
Summary: This study investigates the influence of fracturing fluids with different pH values on the mechanical properties of shale. Through soaking experiments and various testing methods, the changes in shale's mechanical properties after different soaking durations and the variations in shale's microstructure are analyzed. The experimental results demonstrate that acid, neutral, and alkaline fluids have significant effects on the strength and Young's modulus of shale, with different trends observed.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Energy & Fuels
Qiao Lyu, Kaixi Wang, Chenger Hu, Jindong Shi, Jingqiang Tan, Guanglei Zhang, Shefa Chen, P. G. Ranjith
Summary: The study explores the effects of supercritical CO2 and water on the mechanical properties of shale, finding that both lead to a decrease in strength with water immersion having a more significant impact. Additionally, it is observed that dynamic pressure imbibition results in more significant changes to the microstructure and mechanical properties of shale.
Article
Geosciences, Multidisciplinary
Zhongliang Ma, Jingqiang Tan, Lunju Zheng, Chunhua Ni, Ruining Hu, Jianfei Ma
Summary: This study reveals the impact of total component fluids from source rock on reservoir transformation during hydrocarbon evolution through simulation experiments. Under closed conditions, the interaction between fluids and feldspar sandstone leads to the alteration of feldspar minerals and the generation of clay minerals, resulting in reservoir tightness. Additionally, a semi-quantitative evaluation method for feldspar dissolution and porosity was established. The geological characteristics of the Yanchang Formation of the Ordos Basin affect the retention effect of diagenetic fluids, and oil and gas exploration should focus on finding sedimentary sand facies bodies favorable for the preservation of primary pores.
MARINE AND PETROLEUM GEOLOGY
(2022)
Article
Energy & Fuels
Wenquan Xie, Jingqiang Tan, Wenhui Wang, Jianliang Jia, Zhaojun Liu, Jian Wu, Yong Wang, Xueqi Song
Summary: Inertinite in coals contains crucial information on the paleo-wildfire history and its relationship with local ecosystem evolution. This study investigates the Middle Jurassic coal seams of the Shimengou Formation in the Qaidam Basin and identifies abundant evidence of paleo-wildfires, including inertinite and combustion-derived polycyclic aromatic hydrocarbons. These findings confirm the existence of widespread wildfires during the late Middle Jurassic period and suggest a high level of atmospheric oxygen concentration. The study also reveals that incidental mercury emissions from wildfires contribute to the mercury enrichment in coal seams, providing insights into the abnormal enrichment of mercury in coal.
INTERNATIONAL JOURNAL OF COAL GEOLOGY
(2022)
Article
Energy & Fuels
Chenger Hu, Jingqiang Tan, Qiao Lyu, Gan Feng, Jindong Shi, Kaixi Wang, Zhanghu Wang
Summary: This study investigates the interaction between fracturing fluid and shale during hydraulic fracturing. The results show that the fluid-shale reaction is time-dependent, and the dissolved minerals and pH values vary with time. The dissolution of minerals can enhance the porosity and gas adsorption capacity of shale, but secondary precipitation during long-term experiments can block pores and decrease the shale's porosity and hydraulic characteristics.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2022)
Article
Environmental Sciences
Jiaqing Zeng, Wenshun Ke, Min Deng, Jingqiang Tan, Chuxuan Li, Yizhi Cheng, Shengguo Xue
Summary: Smelting activities are the main pathway for releasing heavy metals into the soil-groundwater environment. This study conducted a comprehensive investigation of soil from an abandoned Zn smelting site and quantified the factors affecting heavy metal pollution. The results showed severe soil contamination and identified potential pollution sources and soil permeability as the main drivers for heavy metal distribution and accumulation.
JOURNAL OF ENVIRONMENTAL SCIENCES
(2023)
Article
Geosciences, Multidisciplinary
Weijiao Ma, Jinbu Li, Min Wang
Summary: The petroleum resource assessment obtained from laboratory tests on old core samples tends to underestimate the in situ resources. This study investigates the hydrocarbon loss and restoration by comparing preserved and exposed core samples. It is found that previous studies have severely underestimated the in situ hydrocarbon potential due to factors such as sample crushing and crucible waiting. A new restoration model is proposed to compensate for these losses.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Shaoyun Chen, Yongqiang Yang, Longwei Qiu, Xiaojuan Wang, Erejep Habilaxim
Summary: Quartz cement is an important authigenic mineral in the tight sandstones of the Shaximiao Formation in the Sichuan Basin. This study analyzed the silicon sources of the quartz cement using mineralogical, fluid inclusion, and geochemical data. The results showed that smectite alteration and dissolution of aluminosilicate minerals were the primary sources of silicon for quartz cementation. Contributions from volcanic material hydrolysis and pressure solution were relatively minor. The presence of chlorite films inhibited the development of quartz overgrowths and had minimal impact on reservoir quality.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Xing Jian, Ping Guan, Ling Fu, Wei Zhang, Xiaotian Shen, Hanjing Fu, Ling Wang
Summary: This study presents a synthesis of new detrital zircon dating results and published data from the Cenozoic Qaidam basin, revealing the spatiotemporal variation of detrital zircon age populations and supporting models of synchronous deformation in northern Tibet. The study emphasizes the importance of considering textural and sedimentological parameters in zircon provenance interpretations, as well as the need for integrated provenance analysis involving other detritus components.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
A. Peketi, G. Sriram, A. Mazumdar, P. Dewangan, A. Zatale, V. Rajurkar, Gayatri Shirodkar, V. Mahale, V. Yatheesh
Summary: This study investigates 13 submarine seamounts in the southern Andaman volcanic arc and observes evidence of hydrothermal activity in one of the seamounts. The evidence includes plumes rich in dissolved gases, live chemosymbiotic organisms, and the deposition of neoforming minerals. These observations suggest the development of a new hydrothermal field in the least explored Andaman Sea.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Yanxian Zhu, Zhiliang He, Xiaowen Guo, Long Li, Sheng He, Jian Gao, Shuangjian Li, Huili Li
Summary: This study investigates the fluid evolution history of the hydrothermal dolomite reservoir in the Middle Permian Maokou Formation in the Sichuan Basin. The results reveal the diagenetic sequences, mineral origins, salinity history, and pressure evolution using various analytical techniques. The findings provide important insights into the gas charge, escape, and preservation conditions of the reservoir.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Rafaella de Carvalho Antunes, Julia Campos Guerrero, Ricardo Jorge Jahnert
Summary: This study presents a detailed sedimentary model and identifies various sedimentary facies associations in the coquina deposits of the Itapema Formation in the offshore pre-salt Buzios Field of the Santos Basin. These facies associations were primarily influenced by waves and currents and reflect a complex depositional system.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Kang Meng, Tongwei Zhang, Deyong Shao, Xiuyan Liu, Hui Song, Heng Peng
Summary: In this study, an integrated method of measuring optical reflectance and Raman spectroscopy is proposed to accurately determine the thermal maturity of Lower Cambrian shales in South China. The results show that this method is reliable and effective, and it has important implications for analyzing overmature shale.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Mohamed A. K. El-Ghali, Olga Shelukhina, Iftikhar Ahmed Abbasi, Mohamed S. H. Moustafa, Osman Salad Hersi, Numair A. Siddiqui, Khalid Al-Ramadan, Abdullah Alqubalee, Abdulwahab Muhammad Bello, Abduljamiu O. Amao
Summary: This study employs an integrated depositional and sequence stratigraphic approach to assess the control of diagenesis on reservoir porosity of a hybrid-energy delta system. The study focuses on the Barik Formation in the Haushi-Huqf region of Central Oman, which represents a highstand system tract of a hybrid-energy delta. The assessments reveal that the reservoir porosity is controlled by various degrees of diagenetic processes, including mechanically infiltrated clays and kaolinitization of silicate grains.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Xiaocan Yu, Chunlian Wang, Hua Huang, Kai Yan
Summary: Oilfield brines are a significant alternative lithium resource. This study investigates the metallogenic characteristics and enrichment process of oilfield brines from the Jianghan Basin, central China using chemical and multi-isotope data. The results suggest that lithium enrichment in these brines is the result of interaction with clastic host rocks and dilution by meteoric water.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Jianghao Qiao, Xiwu Luan, Thanuja D. Raveendrasinghe, Yintao Lu, Guozhang Fan, Xinyuan Wei, Long Jin, Jian Yin, Haozhe Ma, Lushan Jiang
Summary: This study investigates the Tanintharyi passive continental margin in the Andaman Sea and reveals the potential of the Oligocene/Early Miocene carbonate platform in the region as a significant hydrocarbon reservoir. It also examines the influence of changes in sedimentary facies and the tectonic setting of the Andaman Sea on the evolution of pockmarks.
MARINE AND PETROLEUM GEOLOGY
(2024)
Article
Geosciences, Multidisciplinary
Anastasios Nikitas, Georgios Makrodimitras, Maria V. Triantaphyllou, Nikolaos Pasadakis, Kimon Christanis, Stavros Kalaitzidis, Grigoris Rousakis, Ioannis Panagiotopoulos, Alexandra Gogou, Alexandros Papadopoulos, Efthimios Tartaras, Aristofanis Stefatos
Summary: Due to the lack of deep wells in the broader region, studying mud volcanic deposits can improve the geological understanding of the Mediterranean Ridge. In this study, biostratigraphic and geochemical analyses were performed on mud breccia deposits from five Mud Volcanoes in the central MR. The results indicate the origin of these deposits and provide insights into the source rock potential. Seismic data is also used to determine the distribution of major lithostratigraphic formations.
MARINE AND PETROLEUM GEOLOGY
(2024)