气候变化领域集成服务门户(CCPortal): Deformation Memory in the Lithosphere: A Comparison of Damage-dependent Weakening and Grain-Size Sensitive Rheologies

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DOI	10.1029/2020JB020335
	Deformation Memory in the Lithosphere: A Comparison of Damage-dependent Weakening and Grain-Size Sensitive Rheologies
	Fuchs L.; Becker T.W.
发表日期	2021
ISSN	21699313
卷号	126 期号:1
英文摘要	Strain localization in the lithosphere and the formation, evolution, and maintenance of resulting plate boundaries play a crucial role in plate tectonics and thermo-chemical mantle convection. Previously activated lithospheric deformation zones often appear to maintain a “memory” of weakening, leading to tectonic inheritance within plate reorganizations including the Wilson cycle. Different mechanisms have been proposed to explain such strain localization, but it remains unclear which operates on what spatio-temporal scales, and how to best incorporate them in large-scale mantle convection models. Here, we analyze two candidates, (1), grain-size sensitive rheology and, (2), damage-style parameterizations of yield, stress which are sometimes used to approximate the former. Grain-size reduction due to dynamic recrystallization can drive localization in the ductile domain, and grain growth provides a time-dependent rheological hardening component potentially enabling the preservation of rheological heterogeneities. We compare the dynamic weakening and hardening effects as well as the timescales of strength evolution for a composite rheology including grain-size dynamics with a pseudo-plastic rheology including damage- (or “strain”-) dependent weakening. We explore the implications of different proposed grain-size evolution laws, and test to which extent strain-dependent rheologies can mimic the weakening and hardening effects of the more complex micro-physical behavior. Such an analysis helps to better understand the parallels and differences between various strain-localization modeling approaches used in different tectonics and geodynamics communities. More importantly, our results contribute to efforts to identify the key ingredients of strain-localization and damage hysteresis within plate tectonics and how to represent those in planetary-scale modeling. © 2020. The Authors.
英文关键词	damage memory; grain-size evolution; strain localization; strain-dependent 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/187401
作者单位	Institute for Geosciences, Department of Geosciences, Goethe University, Frankfurt, Germany; Jackson School of Geosciences, Institute for Geophysics, The University of Texas at Austin, Austin, TX, United States; Department of Geological Sciences, Jackson School of Geoscience, The University of Texas at Austin, Austin, TX, United States
推荐引用方式 GB/T 7714	Fuchs L.,Becker T.W.. Deformation Memory in the Lithosphere: A Comparison of Damage-dependent Weakening and Grain-Size Sensitive Rheologies[J],2021,126(1).
APA	Fuchs L.,&Becker T.W..(2021).Deformation Memory in the Lithosphere: A Comparison of Damage-dependent Weakening and Grain-Size Sensitive Rheologies.Journal of Geophysical Research: Solid Earth,126(1).
MLA	Fuchs L.,et al."Deformation Memory in the Lithosphere: A Comparison of Damage-dependent Weakening and Grain-Size Sensitive Rheologies".Journal of Geophysical Research: Solid Earth 126.1(2021).