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DOI	10.1029/2020JB020405
	The Role of Shear Fabric in Controlling Breakdown Processes During Laboratory Slow-Slip Events
	Scuderi M.M.; Tinti E.; Cocco M.; Collettini C.
发表日期	2020
ISSN	21699313
卷号	125 期号:11
英文摘要	Understanding the physical mechanisms at the origin of slow-slip events has been proven a very challenging task. In particular, little is known on the role of fault heterogeneity during slow slip. In this study, we provide evidences that fault fabric controls slip velocity time histories during slow-slip events generated in the laboratory. We performed experiments using a double-direct biaxial shear apparatus and two different fault gouges, homogeneous quartz powder, and heterogeneous anhydrite/dolomite mixture. We measure details of fault slip to resolve the slip velocity function and volumetric deformation that, coupled with an analysis of the resulting microstructure, allow us to infer the mechanical processes at play. Our results show that slow-slip events can be generated for both fault gouges when k ~ kc with similar values of breakdown work. The shear fabric exerts a strong influence during the coseismic breakdown stage. In quartz, where most of the slip occurs on a very localized slipping surface, the peak slip velocity is attained near the final stage of friction breakdown and therefore a relevant amount of the mechanical work is absorbed during slip acceleration. In anhydrite/dolomite mixture, the peak slip velocity is suddenly reached after a relatively small drop in friction, accompanied by fault dilation, implying that most of the mechanical work is absorbed during slip deceleration. For anhydrite/dolomite mixture these results are likely related to heterogeneous slip distribution along the observed foliation. Taken together, these observations suggest that the mechanics of slow-slip events depends on shear zone fabric. ©2020. The Authors.
英文关键词	microstructure; RSF friction; slip velocity function; slow-slip events
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187509
作者单位	Dipartimento di Scienze della Terra, La Sapienza Università di Roma, Rome, Italy; Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy
推荐引用方式 GB/T 7714	Scuderi M.M.,Tinti E.,Cocco M.,et al. The Role of Shear Fabric in Controlling Breakdown Processes During Laboratory Slow-Slip Events[J],2020,125(11).
APA	Scuderi M.M.,Tinti E.,Cocco M.,&Collettini C..(2020).The Role of Shear Fabric in Controlling Breakdown Processes During Laboratory Slow-Slip Events.Journal of Geophysical Research: Solid Earth,125(11).
MLA	Scuderi M.M.,et al."The Role of Shear Fabric in Controlling Breakdown Processes During Laboratory Slow-Slip Events".Journal of Geophysical Research: Solid Earth 125.11(2020).