气候变化领域集成服务门户(CCPortal): Thermal Weakening Friction During Seismic Slip: Experiments and Models With Heat Sources and Sinks

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DOI	10.1029/2020JB020652
	Thermal Weakening Friction During Seismic Slip: Experiments and Models With Heat Sources and Sinks
	Nielsen S.; Spagnuolo E.; Violay M.; Di Toro G.
发表日期	2021
ISSN	21699313
卷号	126 期号:5
英文摘要	Experiments that systematically explore rock friction under crustal earthquake conditions reveal that faults undergo abrupt dynamic weakening. Processes related to heating and weakening of fault surfaces have been invoked to explain pronounced velocity weakening. Both contact asperity temperature Ta and background temperature T of the slip zone evolve significantly during high-velocity slip due to heat sources (frictional work), heat sinks (e.g., latent heat of decomposition processes), and diffusion. Using carefully calibrated High-Velocity Rotary Friction experiments, we test the compatibility of thermal weakening models: (1) a model of friction based only on T in an extremely simplified, Arrhenius-like thermal dependence; (2) a flash heating model which accounts for the evolution of both V and T; (3) same but including heat sinks in the thermal balance; and (4) same but including the thermal dependence of diffusivity and heat capacity. All models reflect the experimental results but model (1) results in unrealistically low temperatures and model (2) reproduces the restrengthening phase only by modifying the parameters for each experimental condition. The presence of dissipative heat sinks in stage (3) significantly affects T and reflects on the friction, allowing a better joint fit of the initial weakening and final strength recovery across a range of experiments. Temperature is significantly altered by thermal dependence of (4). However, similar results can be obtained by (3) and (4) by adjusting the energy sinks. To compute temperature in this type of problem, we compare the efficiency of three different numerical approximations (finite difference, wavenumber summation, and discrete integral). © 2021. The Authors.
英文关键词	earthquakes; flash weakening; friction; numerical efficiency; thermal diffusion; thermal weakening
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/187138
作者单位	Department of Earth Sciences, Durham University, Durham, United Kingdom; Sismologia e Tettonofisica, Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy; Faculté de l’Environnement Naturel, Architectural et Construit (ENAC), Laboratory of Experimental Rock Mechanics (LEMR), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland; Dipartimento di Geoscienze, Università degli Studi di Padova, Padova, Italy
推荐引用方式 GB/T 7714	Nielsen S.,Spagnuolo E.,Violay M.,et al. Thermal Weakening Friction During Seismic Slip: Experiments and Models With Heat Sources and Sinks[J],2021,126(5).
APA	Nielsen S.,Spagnuolo E.,Violay M.,&Di Toro G..(2021).Thermal Weakening Friction During Seismic Slip: Experiments and Models With Heat Sources and Sinks.Journal of Geophysical Research: Solid Earth,126(5).
MLA	Nielsen S.,et al."Thermal Weakening Friction During Seismic Slip: Experiments and Models With Heat Sources and Sinks".Journal of Geophysical Research: Solid Earth 126.5(2021).