Remotely triggered nonvolcanic tremor in Sumbawa, Indonesia

Author(s)
Florian Fuchs, Matteo Lupi, Stephen A. Miller
Abstract

We present, for the first time, evidence for triggered tremor beneath the island of Sumbawa, Indonesia. We show triggered tremor in response to three teleseismic earthquakes: the M

w 9.0 2011 Tohoku earthquake and two oceanic strike-slip earthquakes (M

w 8.6 and M

w 8.2) offshore of Sumatra in 2012. We constrain an apparent triggering threshold of 1 mm/s ground velocity that corresponds to about 8 kPa dynamic stress. Peak tremor amplitudes of about 180 nm/s are observed, and scale with the ground velocity induced by the remote earthquakes. Triggered tremor responds to 45-65 s period surface waves and predominantly correlates with Rayleigh waves, even though the 2012 oceanic events have stronger Love wave amplitudes. We could not locate the tremor because of minimal station coverage, but data indicate several potential source volumes including the Flores Thrust, the Java subduction zone, or Tambora volcano.

Organisation(s)
Department of Meteorology and Geophysics
External organisation(s)
Eidgenössische Technische Hochschule Zürich, Université de Neuchâtel
Journal
Geophysical Research Letters
Volume
41
Pages
4185-4193
No. of pages
9
ISSN
0094-8276
DOI
https://doi.org/10.1002/2014GL060312
Publication date
2014
Peer reviewed
Yes
Austrian Fields of Science 2012
105106 Geodynamics, 105122 Seismic, 105102 General geophysics
ASJC Scopus subject areas
Geophysics, General Earth and Planetary Sciences
Portal url
https://ucrisportal.univie.ac.at/en/publications/406bbe3b-d8fe-45b4-a971-1d04a70409bb