Title | Newly detected earthquakes in the Cascadia subduction zone linked to seamount subduction and deformed upper plate |
Publication Type | Journal Article |
Year of Publication | 2018 |
Authors | Morton EA, Bilek SL, Rowe CA |
Journal | Geology |
Volume | 46 |
Pagination | 943–946 |
Date Published | 09/2018 |
ISSN | 0091-7613 |
Abstract | Data from an amphibious seismic network in Cascadia (northwest North America) provide unique near-source observations to assess the influence of subducting topography on seismicity. Using subspace detection, we detect and locate 222 events in two separate clusters, near a subducted seamount and a possibly accreted seamount. Seismicity in both clusters is largely shallower than the plate interface and exhibits occasional swarm-like behavior. This implies that the seamount is subducting aseismically via weak coupling with the overriding plate, while earthquakes in the upper plate arise from a high degree of fracturing due to seamount interaction, and the accreted seamount induced similar fracturing before off-scraping. |
URL | https://doi.org/10.1130/G45354.1 |
DOI | 10.1130/G45354.1 |