skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on June 26, 2019

Title: Source complexity of the 2015 Mw 7.9 Bonin earthquake

The 30 May 2015 Mw 7.9 Bonin earthquake, one of the largest and deepest earthquakes ever recorded by modern seismology, provides a unique opportunity to study the source process and physical mechanisms of deep-focus earthquakes. We develop a novel back-projection technique that allows source imaging in full three-dimensional space with high depth resolution. Our results indicate an initial SW-NE bilateral source propagation followed by a northwest source extension. The multiple-source inversion reveals a two-step source process with propagating directions near-perpendicular to each other, consistent with the 3D back-projection result. The spatial distribution and focal mechanisms of the sub-events cannot be modeled by a single planar rupture, which may display a curved rupture plane or sub-events crossing multiple fault interfaces. Thus, the complex source process can be best explained by stress or structure heterogeneity within the deep slab.
Authors:
ORCiD logo [1] ; ORCiD logo [2] ;  [2] ; ORCiD logo [3]
  1. Stony Brook Univ., NY (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Univ. of California, Los Angeles, CA (United States)
  3. Stony Brook Univ., NY (United States); Univ. of Science and Technology of China, Hefei (China). Lab. of Seismology and Physics of Earth's Interior and School of Earth and Space Sciences
Publication Date:
Report Number(s):
LA-UR-16-28661
Journal ID: ISSN 1525-2027
Grant/Contract Number:
AC52-06NA25396; EAR 1214215; EAR 1614609; EAR-1261681
Type:
Accepted Manuscript
Journal Name:
Geochemistry, Geophysics, Geosystems
Additional Journal Information:
Journal Name: Geochemistry, Geophysics, Geosystems; Journal ID: ISSN 1525-2027
Publisher:
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE; National Science Foundation (NSF)
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; deep earthquake; source complexity; back-projection; multiple-source inversion; slab heterogeneity
OSTI Identifier:
1459820