Systematic deficiency of aftershocks in areas of high coseismic slip for large subduction zone earthquakes

作者：Nadav Wetzler, Thorne Lay, E. E. Brodsky, Hiroo Kanamori · 发表于：Science Advances · 年份：2018 · DOI：10.1126/sciadv.aao3225 · 被引用次数：111 · 研究领域：earthquake and tectonic studies、High-pressure geophysics and materials、Geological and Geochemical Analysis

≥ 5.2 are located within the slip regions of the mainshock ruptures and few are located in peak slip regions, allowing for uncertainty in the slip models. For the preferred models, cumulative deficiency of aftershocks within the central three-quarters of the scaled slip regions ranges from 15 to 45%, increasing with the total number of observed aftershocks. The spatial gradients of the mainshock coseismic slip concentrate residual shear stress near the slip zone margins and increase stress outside the slip zone, driving both interplate and intraplate aftershock occurrence near the periphery of the mainshock slip. The shear stress reduction in large-slip regions during the mainshock is generally sufficient to preclude further significant rupture during the aftershock sequence, consistent with large-slip areas relocking and not rupturing again for a substantial time.