气候变化领域集成服务门户(CCPortal): Earthquake Sequence Dynamics at the Interface Between an Elastic Layer and Underlying Half-Space in Antiplane Shear

CCPortal

DOI	10.1029/2020JB020007
	Earthquake Sequence Dynamics at the Interface Between an Elastic Layer and Underlying Half-Space in Antiplane Shear
	Abrahams L.S.; Allison K.L.; Dunham E.M.
发表日期	2020
ISSN	21699313
卷号	125 期号:12
英文摘要	We quantify sliding stability and rupture styles for a horizontal interface between an elastic layer and stiffer elastic half-space with a free surface on top and rate-and-state friction on the interface. This geometry includes shallowly dipping subduction zones, landslides, and ice streams. Specific motivation comes from quasiperiodic slow slip events on the Whillans Ice Plain in West Antarctica. We quantify the influence of layer thickness on sliding stability, specifically whether a steadily loaded system produces steady sliding or stick-slip sequences. We do this using both linear stability analysis and nonlinear earthquake sequence simulations. We restrict our attention to the 2-D antiplane shear problem but anticipate that our findings generalize to more complex 2-D in-plane and 3-D problems. Steady sliding with velocity-weakening rate-and-state friction is linearly unstable to Fourier mode perturbations having wavelengths greater than a critical wavelength (λc). We quantify the dependence of λc on the rate-and-state friction parameters, elastic properties, loading, and the layer thickness (H). Confirming previous studies, we find that λc ∝ H1/2 for small H and is independent of H for large H. The linear stability analysis provides insight into nonlinear earthquake sequence dynamics of a nominally velocity-strengthening interface containing a velocity-weakening region of width W. Sequence simulations reveal a transition from steady sliding at small W to stick-slip events when W exceeds a critical width (Wcr), with Wcr ∝ H1/2 for small H. Overall, this study demonstrates that the reduced stiffness of thin layers promotes instability, with implications for sliding dynamics in thin layer geometries. © 2020. American Geophysical Union. All Rights Reserved.
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/187452
作者单位	Department of Geophysics, Stanford University, Stanford, CA, United States; Department of Geology, University of Maryland, College Park, MD, United States; Institute of Computational and Mathematical Engineering, Stanford University, Stanford, CA, United States
推荐引用方式 GB/T 7714	Abrahams L.S.,Allison K.L.,Dunham E.M.. Earthquake Sequence Dynamics at the Interface Between an Elastic Layer and Underlying Half-Space in Antiplane Shear[J],2020,125(12).
APA	Abrahams L.S.,Allison K.L.,&Dunham E.M..(2020).Earthquake Sequence Dynamics at the Interface Between an Elastic Layer and Underlying Half-Space in Antiplane Shear.Journal of Geophysical Research: Solid Earth,125(12).
MLA	Abrahams L.S.,et al."Earthquake Sequence Dynamics at the Interface Between an Elastic Layer and Underlying Half-Space in Antiplane Shear".Journal of Geophysical Research: Solid Earth 125.12(2020).