Article
Energy & Fuels
Lu Ma, Xiaoyang Xu
Summary: This study investigates the mechanical behavior of methane hydrate bearing sediment (MHS) in a laboratory setting, finding that effective stress and hydrate saturation play significant roles in affecting the behavior of MHS. The study introduces a Duncan Chang (D-C) model to describe the mechanical behavior of MHS and determines parameters for this model, showing its effectiveness in predicting mechanics behavior of MHS.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2021)
Article
Energy & Fuels
Weiguo Liu, Dedong Pan, Shi Shen, Zeshao You, Yuechao Zhao, Xiang Sun
Summary: In this experimental study, different sand-water mixing methods were used to prepare specimens of hydrate-bearing sediments, and low-field nuclear magnetic resonance (NMR) technique was employed to investigate the hydrate distribution, which further affects the mechanical properties. The research found that samples with evenly distributed hydrates have higher initial elastic modulus and strength.
Article
Thermodynamics
Yanghui Li, Wenkang Hu, Haoran Tang, Peng Wu, Tao Liu, Zeshao You, Tao Yu, Yongchen Song
Summary: Natural gas hydrate (NGH) is a promising and clean energy source. The development of permafrost hydrate-bearing sediment (HBS) has lower costs, and understanding the mechanical properties is crucial for safe exploitation assessment.
Article
Engineering, Geological
Zeshao You, Yun Hao, Wenkang Hu, Shi Shen, Peng Wu, Yanghui Li
Summary: This study investigates the mechanical behaviors of sandy sediments containing methane hydrate (MH) under excess gas and excess water conditions. The study finds that the influence of MH saturation and effective confining stress on sediment properties are coupled, higher MH saturation leads to strain softening behavior but is hindered by high effective confining stress. The samples with MH exhibit higher stiffness, failure strength, and strain softening tendency under excess gas conditions compared to excess water conditions.
ENGINEERING GEOLOGY
(2023)
Article
Engineering, Geological
Yanlong Li, Lin Dong, Nengyou Wu, Alireza Nouri, Hualin Liao, Qiang Chen, Jianye Sun, Changling Liu
Summary: The study conducted experiments to analyze the mechanical properties of hydrate-bearing sediments with horizontally distributed hydrates, revealing that the behavior of sediment during shearing is mainly determined by the lower hydrate-saturated sub-layer.
ENGINEERING GEOLOGY
(2021)
Article
Engineering, Marine
Xiaobing Lu, Xuhui Zhang, Fangfang Sun, Shuyun Wang, Lele Liu, Changling Liu
Summary: The study indicates that the presence of methane hydrates changes the mechanical properties of hydrate-bearing sediments from plastic failure to brittle failure when the hydrate saturation exceeds 13%; the shear bands can appear as either single oblique lines or inter-crossing lines, with most surfaces of shear bands being non-straight and the widths of the bands being unevenly distributed.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Geological
Masaki Yoshimoto, Sayuri Kimoto
Summary: A study was conducted to investigate the time-dependent properties of CO2 hydrate-bearing sediments using undrained triaxial creep tests. The experiments and modeling revealed that CO2 hydrate-bearing sand specimens exhibited accelerated creep behavior, regardless of hydrate saturation. The elasto-viscoplastic constitutive model considering the cementing effect of hydrates successfully reproduced the undrained creep behavior under relatively high stress levels.
SOILS AND FOUNDATIONS
(2022)
Article
Computer Science, Interdisciplinary Applications
Xiaofeng Dou, Zhichao Liu, Fulong Ning, Yanlong Li, Xiaodong Li, Yingjie Zhao, Wei Hu, Deli Gao
Summary: This study presents a novel approach based on the discrete element method (DEM) to describe the mechanical weakening of cementing-type gas hydrate-bearing sandy sediments (GHBSSs) during hydrate dissociation. The DEM model successfully captures the mechanical weakening behaviors of GHBSSs, and a fitting equation is obtained to describe the relationship among peak strength, initial hydrate saturation, and hydrate dissociation ratio. This study is valuable for evaluating the stability of GHBSSs during hydrate production.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Engineering, Geological
Hua Du, Huie Chen, Qing Wang, Yonggui Luo, Fansheng Kong, Bin Shi
Summary: The mechanical properties of heterogeneous hydrate-bearing sediments have significant engineering implications. In this study, the effects of hydrate-bearing layer thickness and angle on stress-strain behavior and strength parameters were investigated. It was found that increasing layer thickness and decreasing angle resulted in decreased strain-hardening and varying failure strength.
ENGINEERING GEOLOGY
(2023)
Article
Engineering, Geological
Haoyong Qian, Wei Wu, Chengshun Xu, Xiuli Du
Summary: We propose a model that incorporates hydrate saturation and grain breakage to accurately predict the mechanical responses of hydrate-bearing sands. The model introduces a new degradation scalar to account for the effects of hydrate bonding evolution on strength. Validated through laboratory tests, the model also considers the influence of hydrate saturation and relative breakage ratio at high confining pressure.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2023)
Article
Energy & Fuels
Shi Shen, Yanghui Li, Xiang Sun, Lei Wang, Yongchen Song
Summary: This study conducted mechanical experiments to investigate the effects of temperature and pore pressure on methane hydrate-bearing sediments (MHBSs). The results showed that with decreasing temperature and increasing pore pressure, the strength of the samples increased, and the dilatant volumetric strain also increased. The study also established a numerical relation between strength, temperature, and pore pressure.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Geosciences, Multidisciplinary
Shujian Li, Chongyang Wang, Dongming Zhang, Menglai Wang, Fan Zhou, Yisha Pan
Summary: The deterioration mechanism of mechanical properties of phosphate rock under different saturation time was investigated. Laboratory tests, theoretical analysis and neural network modeling were utilized to analyze the degradation mechanism of phosphoric rock samples. The results revealed that water saturation leads to deterioration of mechanical properties. Peak compressive strength and strain gradually decreased with increasing saturation time. The neural network model was established to predict the mechanical properties under different saturation and confining pressure conditions, with an average accuracy of 0.89. The research provides theoretical reference for the deterioration mechanism of confining pressure in water-rich roadway.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Thermodynamics
Weiguo Liu, Qi Song, Peng Wu, Tao Liu, Lei Huang, Shuheng Zhang, Yanghui Li
Summary: This study conducted anisotropic consolidated shearing tests to investigate the mechanical properties of hydrate-bearing clayey-silty sediment. The stress-strain curves exhibited a strain-hardening trend and volumetric contraction. The increasing consolidation stress ratio and effective confining pressure led to higher failure strength, while the internal friction angle was proportional and cohesion was inversely proportional to the consolidation stress ratio.
Article
Chemistry, Physical
Rongtao Yan, Hongfei Yu, Dehuan Yang, Yuancheng Wu, Hao Tang
Summary: This paper investigates the isotropic compression characteristics of methane hydrate-bearing soil (MHBS), showing that the hydrate saturation, temperature, and pore pressure conditions have significant influences on the compressibility and strength of MHBS.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Environmental
Jianwei Li, Yu Zhang, Liang Lin, You Zhou
Summary: This study investigates the mechanical properties of the hydrate-bearing sand-well interface, considering hydrate saturation, hydrate dissociation, and interface roughness. The results show that the strength and cohesion of the interface increase with higher roughness and hydrate saturation, while decrease after hydrate dissolution. A mechanical model is proposed based on statistical damage theory and Duncan-Chang interface constitutive model, which agrees well with experimental results. These findings can provide guidance for stability evaluation of hydrate-bearing reservoirs and exploitation wells.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2023)
Article
Chemistry, Physical
Yusuke Jin, Masato Kida, Jiro Nagao
Summary: This study reports the conformation selectivity of cyclohexanol in a clathrate hydrate and the effect of hydrogen bonds on lattice shrinkage. The results show that cyclohexanol prefers the equatorial conformation over the axial conformation and that the hydrogen bond between cyclohexanol and the water framework causes a reduction in the lattice constant.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Geosciences, Multidisciplinary
Jun Yoneda, Yusuke Jin, Michihiro Muraoka, Motoi Oshima, Kiyofumi Suzuki, William F. Waite, Peter B. Flemings
Summary: The study quantified the petrophysical and geomechanical properties of methane hydrate-bearing sediments in the Gulf of Mexico using pressure-core analysis tools. The results provide a foundation for understanding the natural hydrate system and predicting gas production behavior for future resource development.
Article
Energy & Fuels
Jun Yoneda, Kiyofumi Suzuki, Yusuke Jin, Satoshi Ohtsuki, Timothy S. Collett, Ray Boswell, Yuki Maehara, Norihiro Okinaka
Summary: In this study, the permeability characteristics of hydrate-bearing core samples were investigated using laboratory tests and NMR analysis. The results showed that conventional permeability models underestimated the experimental data, while using a T-2 cutoff of 10 ms and a newly developed hydraulic radius model provided a better fit. Additionally, the gas permeability exhibited rapid changes at high water saturations.
Article
Environmental Sciences
Ji-Hoon Kim, Myong-Ho Park, Dong-Hun Lee, Hirotsugu Minami, Young-Keun Jin, Akihiro Hachikubo, Jin Hur, Jong-Sik Ryu, Moo-Hee Kang, Kwangchul Jang, Masato Kida, Yongwon Seo, Meilian Chen, Jong Kuk Hong, Yungoo Song, Sanghee Park
Summary: We investigated the impact of methane seepage on the pore fluid and methane-derived authigenic carbonate (MDAC) chemistry in the ARAON Mounds in the Chukchi Sea. Our findings show that the high methane flux and related byproducts significantly alter the fluid chemistry and physical properties of the sediment columns. This research improves our understanding and prediction of pore fluid and MDAC chemistry in the Arctic Ocean, particularly in relation to methane seepage caused by global climate change.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Energy & Fuels
Yusuke Jin, Masato Kida, Jiro Nagao
Summary: In this study, a novel hydrate former with the ability to act as a structure II former and a thermodynamic inhibitor is reported. Thiazole, an aromatic five-ringed molecule, forms an sII hydrate crystal with small CH4 and CO2 molecules. The thiazole molecule exhibits guest-host interactions with water frameworks through hydrogen bonding. This molecule, however, cannot form an sII hydrate with the C2H6 molecule and instead functions as a thermodynamic inhibitor for the sI C2H6 hydrate.
Article
Energy & Fuels
Masato Kida, Reiji Fujiwara, Hayato Goda, Hirotoshi Sakagami, Hirotsugu Minami
Summary: This report investigates the separation characteristics of stoichiometric quaternary ammonium salt (QAS) hydrates for methane and carbon dioxide with simulated biogas. The tests were conducted using different QAS hydrates as solid phases at various temperatures and pressures. The results show that the QAS hydrates have selective incorporation of carbon dioxide into the hydrate phase, with tetra-n-butylammonium chloride (TBAC) hydrate exhibiting the highest separation factor. Lowering the initial pressure improves the separation performance of the QAS hydrates, indicating that they can achieve effective separation even at lower pressures.
Article
Thermodynamics
Yusuke Jin, Motoi Oshima, Jiro Nagao
Summary: The size of structure-H clathrate hydrates (sH hydrates) depends on the size of large molecule guest substances (LMGSs). The c-axis in an sH hydrate structure is sensitive to the longest molecular length of the LMGSs. Four new LMGSs for structure-H hydrates containing CH4 were reported: iodocyclopentane (ICP), chlorocycloheptane (ClCHP), bromocycloheptane (BrCHP), and trans-1,4-dichlorocyclohexane (t14DClCH). The temperature shifts of the four LMGS systems from the pure CH4-water system increased in the following order: ICP & SIM < BrCHP (3.7 K) < ClCHP (4.7 K) < t14DClCH (5.1 K).
JOURNAL OF CHEMICAL AND ENGINEERING DATA
(2023)
Article
Engineering, Ocean
Hiroyuki Oyama, Tomoya Ogino, Toru Sato, Hisato Yasuda, Jiro Nagao, Norio Tenma
Summary: It has been discovered that mud flocs and methane hydrate coexist in sediment layers off the coast of Japan. There is concern that the flow of pure water from the dissociation of methane hydrate may break down the mud flocs, leading to sand problems in production wells. This study examined the characteristics of the flocs by observing samples collected from natural cores and testing their mechanical stability in distilled water flow. The flocs were found to mainly consist of silt and were stable under certain flow rates, but decomposed into silt and clay particles when subjected to pressure, suggesting they could be a source of fine particles as underground stress conditions change.
MARINE GEORESOURCES & GEOTECHNOLOGY
(2023)
Article
Energy & Fuels
Yusuke Jin, Masato Kida, Jiro Nagao
Summary: In this study, a novel hydrate former was discovered to act as a structure II (sII) former and thermodynamic inhibitor. Thiazole, an aromatic five-ringed molecule with two heteroatoms, was found to form sII hydrate crystals with small CH4 and CO2 molecules. The guest-host interactions between thiazole and the water frameworks were analyzed, and it was found that thiazole functions as a thermodynamic inhibitor for the structure I (sI) C2H6 hydrate.
Article
Chemistry, Physical
Sanehiro Muromachi, Masato Kida, Masato Morimoto, Shogo Yamane, Satoshi Takeya
Summary: This paper investigates the manipulation of the structure and properties of semiclathrate hydrates. By adjusting the alkyl side chain length of quaternary ammonium salts, the structure and relevant properties of the hydrates can be modified.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
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)
