Anisotropy rather than transverse isotropy in Longmaxi shale and the potential role of tectonic stress

doi:10.1016/j.enggeo.2018.10.018

	Anisotropy rather than transverse isotropy in Longmaxi shale and the potential role of tectonic stress
	Chen, Junhui 1,2; Lan, Hengxing 1,3; Macciotta, Renato 3,4; Wu, Yuming 1; Li, Quanwen 1,2; Zhao, Xiaoxia 1,2
刊名	ENGINEERING GEOLOGY
	2018-12-20
卷号	247 页码:38-47
关键词	Transverse isotropy Mechanical property Anisotropy Gas shale Tectonic stress
ISSN号	0013-7952
DOI	10.1016/j.enggeo.2018.10.018
通讯作者	Lan, Hengxing(lanhx@lreis.ac.cn)
英文摘要	In the last few decades, the recovery of and exploration for shale gas has increased. This has led to increased interest in the mechanical characterization of shale formations as relates to enhancing the conductivity of such formations. Characterization and modeling of these materials typically assumes transverse isotropy associated with the direction of bedding, despite some studies showing anisotropy in these materials. In this work, we evaluate the validity of transverse isotropy for the Longmaxi Shale Formation, which has been targeted for shale gas exploration in China. This evaluation is done through analysis of the macro- and microstructure distribution, confined triaxial tests, and compression and shear wave velocity measurements. These tests were performed parallel and perpendicular to the bedding and in the directions interpreted as the tectonic principal stresses. The effect of tectonic stress on shale anisotropy is also discussed. We found that the assumption of transverse isotropy for the mechanical behavior of the Longmaxi Shale might not be adequate under low confinement stresses. The trends in the measured behavior suggest that transverse isotropy might provide adequate estimations as confinement increases. The data also suggest that tectonic stresses affected the Longmaxi Shale rock mass characteristics at the study site in terms of macro- and microstructure, as well as mechanical properties. The results also indicate that isotropic rocks may show anisotropy in subsurface engineering. Directing more attention to the possible mechanical differences in the field may provide implications for engineering safety.
资助项目	Strategic Priority Research Program of the Chinese Academy of Sciences[XDB10030300] ; National Natural Science Foundation of China[41525010] ; National Natural Science Foundation of China[41472282] ; National Natural Science Foundation of China[41790443]
WOS关键词	VELOCITY ANISOTROPY ; FRACTURE ; PROPAGATION ; PATTERNS ; ROCKS ; BASIN ; GAS
WOS研究方向	Engineering ; Geology
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000453495300004
资助机构	Strategic Priority Research Program of the Chinese Academy of Sciences ; National Natural Science Foundation of China
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/51433]
专题	中国科学院地理科学与资源研究所
通讯作者	Lan, Hengxing
作者单位	1.Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, State Key Lab Resource & Environm Informat Syst, Beijing 100101, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Changan Univ, Sch Geol Engn & Geomat, Xian 710054, Shaanxi, Peoples R China 4.Univ Alberta, Fac Engn, Sch Engn Safety & Risk Management, Edmonton, AB, Canada
推荐引用方式 GB/T 7714	Chen, Junhui,Lan, Hengxing,Macciotta, Renato,et al. Anisotropy rather than transverse isotropy in Longmaxi shale and the potential role of tectonic stress[J]. ENGINEERING GEOLOGY,2018,247:38-47.
APA	Chen, Junhui,Lan, Hengxing,Macciotta, Renato,Wu, Yuming,Li, Quanwen,&Zhao, Xiaoxia.(2018).Anisotropy rather than transverse isotropy in Longmaxi shale and the potential role of tectonic stress.ENGINEERING GEOLOGY,247,38-47.
MLA	Chen, Junhui,et al."Anisotropy rather than transverse isotropy in Longmaxi shale and the potential role of tectonic stress".ENGINEERING GEOLOGY 247(2018):38-47.