Article
Energy & Fuels
Yujie Yuan, Reza Rezaee, Hongyan Yu, Jie Zou, Kouqi Liu, Yihuai Zhang
Summary: The study classified shales into 12 lithofacies and compared the Goldwyer shales with other shale lithofacies, pure clays, and isolated kerogens using various techniques. Results show that the argillaceous OM-rich lithofacies have more interconnected pores with better hydrocarbon storage potential, while other lithofacies and isolated kerogens have their own characteristics in shale gas storage capacities.
Article
Engineering, Civil
Ketan Arora, Marte Gutierrez, Ahmadreza Hedayat, Caichu Xia
Summary: This study reviews the prediction methods for tunnel squeezing in clay-rich rocks and proposes a new methodology to assess ground conditions and squeezing potential using various indicators. By combining the proposed classification system with an existing classification system for ground squeezing condition, an accurate estimate of tunnel strain can be obtained.
Article
Geosciences, Multidisciplinary
Hui Xiao, Nan Xie, Yuanyuan Lu, Tianyue Cheng, Wei Dang
Summary: The study of the pore structure and its controlling factors in shale reservoirs is crucial for the exploration and exploitation of shale gas. This study focused on the effects of organic and inorganic compositions on the pore structure development of Shanxi shale in the Ordos Basin. The results showed that the mineral composition and organic matter type are key factors in determining the pore structure of shale. The pore structure plays a significant role in the characteristics and development potential of shale.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Chemistry, Physical
Jiaqi Chang, Xiaodong Fan, Zhenxue Jiang, Xingmeng Wang, Lei Chen, Jitong Li, Lin Zhu, Chengxiang Wan, Zhixiang Chen
Summary: This study investigated the effects of organic matter, clay minerals and organo-clay composites on the pore structure and pore complexity of shale reservoirs. The results showed that the type and maturity of macerals, illite, kaolinite, and organo-clay composites are the main factors influencing shale pore development. The study also found that different clay mineral types have different effects on shale pore structure and pore complexity.
APPLIED CLAY SCIENCE
(2022)
Article
Geochemistry & Geophysics
Agrinier Pierre, Bonifacie Magali, Bardoux Gerard, Francis Lucazeau, Giunta Thomas, Ader Magali
Summary: Overall, the chlorine isotope fractionation in pore fluid may be controlled by specific fluid-specific processes rather than water-rock exchange reactions. Compaction-induced ion filtration through clay-rich membranes could potentially explain the observed depletion in pore fluid delta Cl-37, with different clay minerals associated with different isotopic fractionation factors. Further experimental work is needed to better understand the role of ion-filtration in fractionating isotopic species in sediment pore waters.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Chemistry, Physical
Kun Yu, Kaidi Zhao, Yiwen Ju
Summary: The low permeability of unconventional reservoirs, particularly coal and clay-rich shale, can significantly impact the production efficiency of methane due to the unique water sensitivity and swelling mechanism of clay minerals. Hydraulic fracturing can enhance the permeability of these reservoirs, with clay-rich shale showing better improvement than coal.
APPLIED CLAY SCIENCE
(2022)
Article
Chemistry, Physical
M. Fleury, T. Gimmi, M. Mazurek
Summary: Non-invasive Nuclear Magnetic Resonance (NMR) techniques were used to evaluate the pore structure, porosity, water mobility, and affinity of various clay systems. The key finding is the determination of pore-size distribution by NMR cryoporometry, which also measured the water volume in pores smaller than 2 nm. Additionally, T2 distributions were found to be not representative of pore-size distributions as water diffused throughout the pore network during the magnetization lifetime.
CLAYS AND CLAY MINERALS
(2022)
Article
Chemistry, Physical
Nikoo Fakhari, Chua Han Bing, Ziad Bennour, Raoof Gholami
Summary: In recent decades, a variety of shale inhibitors have been developed to improve drilling efficiency by reducing clay swelling. Biomolecules and biosurfactants have gained significant attention due to their high inhibition capacity, biodegradability, low toxicity, and compatibility with water-based drilling fluids. This study evaluated the effectiveness of two green surfactants, Flaxseed Protein (FP) and Flaxseed Mucilage (FM), as shale inhibitors through laboratory measurements. The results showed that both surfactants exhibited good functionality and survivability under different temperature conditions, and possessed functional groups that could reduce interfacial tension, alter surface wettability, and encapsulate clays to reduce hydration. Additionally, the compatibility of both surfactants with salt (KCl) was confirmed, and the presence of salts did not affect their functionality. The tests on bentonite dispersion and shale inhibition revealed that FM formed a thin layer around the clay due to its gelling properties, while FP with its positive surface charge adsorbed onto the clay surface, reducing the clay's affinity to interact with water.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Multidisciplinary Sciences
Clement Afagwu, Mohamed Mahmoud, Saad Alafnan, Abdullah Alqubalee, Ammar ElHusseiny, Shirish Patil
Summary: This study investigates the role of clay's elemental concentration, purity, and types on its pore attributes. It is found that kaolinite has the highest N-2 gas capacity and can be used as a good catalytic material for esterification reactions. Montmorillonite has the largest specific surface area in non-micropores and promotes reactivity and cation exchange interaction. The clay samples have negligible micropores.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2022)
Article
Energy & Fuels
Kunjie Li, Shaoqi Kong, Yanxia Liang, Muhammad Ali, Yongfa Zhang, Yuqiong Zhao
Summary: Clay minerals, as a vital component of shale, have a significant impact on the pore structure and gas content of reservoirs. The study analyzed thirteen shale samples from the Qinshui Basin using multiple techniques and found that the principal minerals were quartz, kaolinite, and illite. Different forms of clay minerals, such as compacted, parallel, bent, and tilted structures, were observed, contributing to the heterogeneity, low porosity, and high permeability anisotropy of shale.
Article
Energy & Fuels
Ying Mu, Zhiming Hu, Jin Chang, Xianggang Duan, Yalong Li, Yanran Li, Wente Niu
Summary: This study utilizes nuclear magnetic resonance (NMR) technology and fluid state experiments to analyze the distribution of water in clay minerals and shale and its impact on permeability. The results show that water saturation is the main factor affecting shale seepage capacity, with the existence of bound water film being a significant factor under low water saturation.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2021)
Article
Energy & Fuels
Fangwen Chen, DeCai Liu, Xue Ding, Qiang Zheng, Shuangfang Lu
Summary: A model for pore size distributions contributed by various components in over-mature shale samples was established using experimental results, and its credibility was confirmed. Pores associated with organic matter, clay, and other components in the shale samples primarily distributed in different pore widths ranges.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Chemistry, Physical
Ofri B. Zusman, Amir Perez, Yael G. Mishael
Summary: The research thoroughly investigated the adsorption mechanism of three chemically-diverse micropollutants on CPN, showing that both anionic and cationic exchange sites coexist on the CPN and can adsorb simultaneously without compromising each other. The adsorption of non-ionic micropollutants was enhanced in the presence of charged micropollutants due to a synergistic effect. The study also demonstrated the efficient filtration of effluent organic matter and micropollutants from TWW by CPN columns compared to granular activated carbon columns.
APPLIED CLAY SCIENCE
(2021)
Article
Chemistry, Physical
Pei Li, Jinchuan Zhang, Reza Rezaee, Wei Dang, Xuan Tang, Haikuan Nie, Shijing Chen
Summary: The distribution of pore water in gas shale reservoirs has a significant impact on gas content and resource evaluation. This study found that adsorbed moisture in transitional clay-rich shales can be divided into different types of water in micro- and non-micropores. Additionally, factors such as thermal maturity, total organic carbon, clay, and carbonate are correlated with adsorbed moisture and pore structure.
APPLIED CLAY SCIENCE
(2021)
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
Geochemistry & Geophysics
Zhen-Min Ge, Xiao-Long Huang, Wei Xie, Tobias W. Hofig, Fan Yang, Yang Yu, S. Khogenkumar Singh
Summary: The mantle source composition of the nascent oceanic crust in the central part of the Gulf of California has been investigated using basaltic glass samples. These samples show trace element patterns similar to enriched mid-ocean ridge basalts, suggesting that the nascent oceanic crust in the Guaymas Basin might be generated through partial melting of a depleted mantle source metasomatized by subducted slab materials.
Article
Geochemistry & Geophysics
Jean-Michel Brazier, Katja E. Goetschl, Martin Dietzel, Vasileios Mavromatis
Summary: This study estimated the distribution coefficient of Zn2+ between calcite/aragonite and reactive fluids and found that the growth rate strongly influences D-Zn(2+) in both minerals. Additionally, a linear correlation was found between D-Zn(2+) and the saturation degree of the reactive fluid.
Article
Geochemistry & Geophysics
Ming Lei, Michele Lustrino, Jifeng Xu, Zhiqiang Kang, Zhengfu Guo, Jianlin Chen
Summary: This study presents a comprehensive geochronological, mineralogical, and geochemical analysis of olivine leucitites in the Maiga area of southern Tibet, suggesting that these rocks originate from a carbonated peridotite mantle source and highlighting the possibility of carbonates being recycled deep into the mantle during continental subduction.
Article
Geochemistry & Geophysics
Yuntao Ye, Xiaomei Wang, Huajian Wang, Haifeng Fan, Zhigang Chen, Qingjun Guo, Ziteng Wang, Chaodong Wu, Donald E. Canfield, Shuichang Zhang
Summary: Phosphorus is an essential element for life and its cycle in the ocean is closely connected with the carbon and oxygen cycles. The study of phosphate oxygen isotopes can provide insights into various reactions related to phosphorus. By analyzing carbonate fluorapatite samples from the Mesoproterozoic Era in North China, it was found that the oxygen isotope values were lower compared to modern samples, indicating a warmer climate during that time period and a potential reason for the scarcity of phosphorite.
Article
Geochemistry & Geophysics
Vincent Busigny, Oanez Lebeau, Didier Jezeduel, Carine Chaduteau, Sean Crowe, Magali Ader
Summary: This study conducted high-precision Mo isotope research on hydrothermal metal sulfides from a porphyry copper deposit in Southwest China and found that different stages of mineralization have distinct Mo isotope compositions, providing valuable insights into the behavior of Mo isotopes in magmatic-hydrothermal systems.
Article
Geochemistry & Geophysics
Min Ji, Xiao-Ying Gao, Yong-Fei Zheng, Bing Gong
Summary: The study examines the anatectic mechanisms in the Himalayan orogen, finding that pressure and temperature control the reaction, while water content mainly affects the solid-phase composition. Dehydration and hydration melting likely occur at different depths in the crust. This research provides important insights into the melting processes in collisional orogens.