Seismic evidence for thermal runaway during intermediate-depth earthquake rupture
Name
Prieto_Seismic evidence.pdf
Size
729.82 KB
Format
Adobe PDF
Checksum (MD5)
b90500e02197457fcf3cbcbd98e443ab
Author(s)
Barrett, Sarah A.
Beroza, Gregory C.
Pedraza, Patricia
Blanco, Jose Faustino
Poveda, Esteban
Prieto Gomez, German A.
Florez Torres, Manuel A.
Date Issued
December 2013
Journal
Geophysical Research Letters
Publisher
American Geophysical Union (AGU)
Citation
Prieto, German A., Manuel Florez, Sarah A. Barrett, Gregory C. Beroza, Patricia Pedraza, Jose Faustino Blanco, and Esteban Poveda. “Seismic Evidence for Thermal Runaway During Intermediate-Depth Earthquake Rupture.” Geophysical Research Letters 40, no. 23 (December 6, 2013): 6064–6068. © 2013 American Geophysical Union
Version
Final published version
Abstract
Intermediate-depth earthquakes occur at depths where temperatures and pressures exceed those at which brittle failure is expected. There are two leading candidates for the physical mechanism behind these earthquakes: dehydration embrittlement and self-localizing thermal shear runaway. A complete energy budget for a range of earthquake sizes can help constrain whether either of these mechanisms might play a role in intermediate-depth earthquake rupture. The combination of high stress drop and low radiation efficiency that we observe for M[subscript w] 4–5 earthquakes in the Bucaramanga Nest implies a temperature increase of 600–1000°C for a centimeter-scale layer during earthquake failure. This suggests that substantial shear heating, and possibly partial melting, occurs during intermediate-depth earthquake failure. Our observations support thermal shear runaway as the mechanism for intermediate-depth earthquakes, which would help explain differences in their behavior compared to shallow earthquakes.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1002/2013gl058109
