Laboratory Simulation of Injection-Induced Shear Slip on Saw-Cut Sandstone Fractures under Different Boundary Conditions

doi:10.1007/s00603-021-02689-4

	Laboratory Simulation of Injection-Induced Shear Slip on Saw-Cut Sandstone Fractures under Different Boundary Conditions
	Shen, Nao 1,3; Wang, Lei 2; Li, Xiaochun 3
刊名	ROCK MECHANICS AND ROCK ENGINEERING
	2021-11-02
页码	21
关键词	Laboratory fault (fracture) Fluid injection Shear slip Induced seismicity Constant piston displacement (CPD) test Constant shear stress (CSS) test
ISSN号	0723-2632
DOI	10.1007/s00603-021-02689-4
英文摘要	It is widely acknowledged that induced earthquakes may be linked to the fluid mass injection into the subsurface in a manner of reactivating preexisting natural faults. To better understand the potential effect of tectonic boundary conditions on induced fault slip behavior, we performed injection-induced shear slip experiments on critically stressed saw-cut sandstone samples under the conditions of constant piston displacement (CPD test) and of constant shear stress (CSS test) at confining pressure of 10 MPa and 15 MPa, respectively. In response to the low fluid pressurization rate of 0.1 MPa/min, the artificial fractures (faults) show a slow slip velocity (< 0.1 mu m/s) accompanied by a linear drop of shear stress in CPD tests, whereas a faster slip velocity (< 5 mu m/s) and a larger slip distance are observed in the subsequent CSS tests. Our experimental results indicate that the laboratory fractures slide stably in response to fluid overpressure during the two tests, supported by the experimentally measured rate-and-state frictional parameters and linear stability analysis. As the confining pressure applied increases from 10 to 15 MPa, the fractures show a considerable decrease in hydraulic diffusivity. Also, the fluid pressure heterogeneity is found to be affected by slip velocity in CSS tests at both confining pressures. We interpret this as a result of the local fluid depressurization that potentially occurs far away from injection end due to the rapid shear-enhanced dilation. In addition, the complete energy budget components associated with fluid-induced fracture slip in the context of CPD and CSS tests, respectively, have been quantitatively evaluated. Our experimental observations highlight that injection-induced fracture slip behavior is closely related not only to the applied effective normal stress, but also to tectonic boundary conditions.
资助项目	National Key R&D Program of China[2019YFE0100100] ; National Natural Science Foundation of China[41972316]
WOS研究方向	Engineering ; Geology
语种	英语
出版者	SPRINGER WIEN
WOS记录号	WOS:000713548400001
内容类型	期刊论文
源URL	[http://119.78.100.198/handle/2S6PX9GI/28358]
专题	中科院武汉岩土力学所
通讯作者	Li, Xiaochun
作者单位	1.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 2.GFZ German Res Ctr Geosci, Helmholtz Ctr Potsdam, D-14473 Potsdam, Germany 3.Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China
推荐引用方式 GB/T 7714	Shen, Nao,Wang, Lei,Li, Xiaochun. Laboratory Simulation of Injection-Induced Shear Slip on Saw-Cut Sandstone Fractures under Different Boundary Conditions[J]. ROCK MECHANICS AND ROCK ENGINEERING,2021:21.
APA	Shen, Nao,Wang, Lei,&Li, Xiaochun.(2021).Laboratory Simulation of Injection-Induced Shear Slip on Saw-Cut Sandstone Fractures under Different Boundary Conditions.ROCK MECHANICS AND ROCK ENGINEERING,21.
MLA	Shen, Nao,et al."Laboratory Simulation of Injection-Induced Shear Slip on Saw-Cut Sandstone Fractures under Different Boundary Conditions".ROCK MECHANICS AND ROCK ENGINEERING (2021):21.