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DOI	10.1029/2019GL085491
	Snow Mechanics Near the Ductile-Brittle Transition: Compressive Stick-Slip and Snow Microquakes
	Löwe H.; Zaiser M.; Mösinger S.; Schleef S.
发表日期	2020
ISSN	0094-8276
卷号	47 期号:4
英文摘要	The rate-dependent mechanical response of snow is commonly believed to directly inherit the ductile-to-brittle transition (DBT) from the viscoplastic ice matrix. Recent work has however stressed the impact of microstructure evolution by rapid sintering during deformation. To understand these phenomena we have conducted deformation-controlled compression experiments in an X-ray tomography stage. By varying the strain rate over 3 orders of magnitude, we find an intermediate regime where the stress response changes from smooth to serrated behavior. This regime is accompanied by microstructure quakes associated with strain localization bands in the sample interior. To interpret the results we developed a minimal, scalar model with a rate-dependent, elastoplastic constitutive law and healing which falls into the general class of rate-and-state models. The model correctly predicts the range of the instability as well as amplitude and frequency of the serrations and reveals a formal equivalence of the observed (compressive) stick-slip with seismic faults. ©2020. The Authors.
英文关键词	Deformation; Imaging systems; Microstructure; Sintering; Slip forming; Snow; Stick-slip; Tomography; X rays; Compression experiments; Ductile brittle transition; Ductile to brittle transitions; Intermediate regimes; Mechanical response; Micro-structure evolutions; Strain localizations; X-ray tomography; Strain rate; brittle deformation; ductile deformation; instability; microstructure; sinter; snow; softening; stick-slip; viscoplasticity; X-ray tomography
语种	英语
来源期刊	Geophysical Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/170646
作者单位	WSL Institute of Snow and Avalanche Research SLF, Davos, Switzerland; Department of Materials Science, University of Erlangen-Nuremberg, Fürth, Germany
推荐引用方式 GB/T 7714	Löwe H.,Zaiser M.,Mösinger S.,et al. Snow Mechanics Near the Ductile-Brittle Transition: Compressive Stick-Slip and Snow Microquakes[J],2020,47(4).
APA	Löwe H.,Zaiser M.,Mösinger S.,&Schleef S..(2020).Snow Mechanics Near the Ductile-Brittle Transition: Compressive Stick-Slip and Snow Microquakes.Geophysical Research Letters,47(4).
MLA	Löwe H.,et al."Snow Mechanics Near the Ductile-Brittle Transition: Compressive Stick-Slip and Snow Microquakes".Geophysical Research Letters 47.4(2020).