| Summary: | Large compressional-faulting earthquakes located relatively deep in oceanic lithosphere entering subduction zones are primarily caused by plate bending stress, but their timing, depth extent and size can be influenced by temporally-varying shear stress on the plate boundary. The 25 March 2020 M_W 7.5 event in the Pacific plate seaward of Paramushir Island (northern Kuril Islands), is among the largest recorded events of this type. Its rupture extends along a large-slip region in the southwestern portion of the 1952 Kamchatka M_W 9.0 rupture zone. This region has somewhat lower interplate coupling than the megathrust fault along Kamchatka to the northeast, but there could be 68 yrs of strain accumulation. The 2020 event is considered in the context of the 24 recorded major (M_W ≥ 7.0) near-trench intraplate compressional-faulting events. An updated compilation of temporally varying near-trench intraslab faulting relative to major interplate ruptures indicates that the stress cycles on the plate boundary influence both extensional and compressional near-trench faulting caused by plate bending. Particularly noteworthy are such events seaward of areas presumed to be in an advanced stage of their seismic cycle, including relatively shallow compressional events along the 1944 M_W 8.1 Tonankai, Japan rupture zone, along with activity along the 1952 Kamchatka and 1922 Chile rupture zones. © 2020 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Received 26 September 2020, Revised 8 December 2020, Accepted 16 December 2020, Available online 5 January 2021. Teleseismic waveforms were downloaded from the Incorporated Research Institutions for Seismology (IRIS) data management center (http://ds.iris.edu/wilber3/find_event). Global Centroid Moment Tensor Solutions are from https://www.globalcmt.org/CMTsearch.html. We use the earthquake catalog from National Earthquake Information Center at U.S. Geological Survey (USGS-NEIC) ...
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