Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes

Abstract The 2012 East Indian Ocean earthquake (Mw 8.6), so far the largest intraoceanic plate strike‐slip event ever recorded, modulated tectonic tremors in the Cascadia subduction zone. The rate of tremor activity near Vancouver Island increased by about 1.5 times from its background level during...

Full description

Saved in:
Bibliographic Details
Main Authors: Bhaskar Kundu, Abhijit Ghosh, Manuel Mendoza, Roland Bürgmann, V. K. Gahalaut, Dipankar Saikia
Format: Article
Language:English
Published: Wiley 2016-09-01
Series:Geophysical Research Letters
Subjects:
Online Access:https://doi.org/10.1002/2016GL069755
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850134534607077376
author Bhaskar Kundu
Abhijit Ghosh
Manuel Mendoza
Roland Bürgmann
V. K. Gahalaut
Dipankar Saikia
author_facet Bhaskar Kundu
Abhijit Ghosh
Manuel Mendoza
Roland Bürgmann
V. K. Gahalaut
Dipankar Saikia
author_sort Bhaskar Kundu
collection DOAJ
description Abstract The 2012 East Indian Ocean earthquake (Mw 8.6), so far the largest intraoceanic plate strike‐slip event ever recorded, modulated tectonic tremors in the Cascadia subduction zone. The rate of tremor activity near Vancouver Island increased by about 1.5 times from its background level during the passage of seismic waves of this earthquake. In most cases of dynamic modulation, large‐amplitude and long‐period surface waves stimulate tremors. However, in this case even the small stress change caused by body waves generated by the 2012 earthquake modulated tremor activity. The tremor modulation continued during the passage of the surface waves, subsequent to which the tremor activity returned to background rates. Similar tremor modulation is observed during the passage of the teleseismic waves from the Mw 8.2 event, which occurs about 2 h later near the Mw 8.6 event. We show that dynamic stresses from back‐to‐back large teleseismic events can strongly influence tremor sources.
format Article
id doaj-art-d440e47490a04e9788656bf951542ef1
institution OA Journals
issn 0094-8276
1944-8007
language English
publishDate 2016-09-01
publisher Wiley
record_format Article
series Geophysical Research Letters
spelling doaj-art-d440e47490a04e9788656bf951542ef12025-08-20T02:31:42ZengWileyGeophysical Research Letters0094-82761944-80072016-09-0143179009901710.1002/2016GL069755Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakesBhaskar Kundu0Abhijit Ghosh1Manuel Mendoza2Roland Bürgmann3V. K. Gahalaut4Dipankar Saikia5Department of Earth and Atmospheric Sciences NIT Rourkela Rourkela IndiaDepartment of Earth Sciences University of California Riverside California USADepartment of Earth Sciences University of California Riverside California USADepartment of Earth and Planetary Science University of California Berkeley California USANational Centre for Seismology Ministry of Earth Sciences New Delhi IndiaIndian National Centre for Ocean Information Services Hyderabad IndiaAbstract The 2012 East Indian Ocean earthquake (Mw 8.6), so far the largest intraoceanic plate strike‐slip event ever recorded, modulated tectonic tremors in the Cascadia subduction zone. The rate of tremor activity near Vancouver Island increased by about 1.5 times from its background level during the passage of seismic waves of this earthquake. In most cases of dynamic modulation, large‐amplitude and long‐period surface waves stimulate tremors. However, in this case even the small stress change caused by body waves generated by the 2012 earthquake modulated tremor activity. The tremor modulation continued during the passage of the surface waves, subsequent to which the tremor activity returned to background rates. Similar tremor modulation is observed during the passage of the teleseismic waves from the Mw 8.2 event, which occurs about 2 h later near the Mw 8.6 event. We show that dynamic stresses from back‐to‐back large teleseismic events can strongly influence tremor sources.https://doi.org/10.1002/2016GL069755CascadiaEast Indian Ocean earthquaketremorVancouver Island
spellingShingle Bhaskar Kundu
Abhijit Ghosh
Manuel Mendoza
Roland Bürgmann
V. K. Gahalaut
Dipankar Saikia
Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes
Geophysical Research Letters
Cascadia
East Indian Ocean earthquake
tremor
Vancouver Island
title Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes
title_full Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes
title_fullStr Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes
title_full_unstemmed Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes
title_short Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes
title_sort tectonic tremor on vancouver island cascadia modulated by the body and surface waves of the mw 8 6 and 8 2 2012 east indian ocean earthquakes
topic Cascadia
East Indian Ocean earthquake
tremor
Vancouver Island
url https://doi.org/10.1002/2016GL069755
work_keys_str_mv AT bhaskarkundu tectonictremoronvancouverislandcascadiamodulatedbythebodyandsurfacewavesofthemw86and822012eastindianoceanearthquakes
AT abhijitghosh tectonictremoronvancouverislandcascadiamodulatedbythebodyandsurfacewavesofthemw86and822012eastindianoceanearthquakes
AT manuelmendoza tectonictremoronvancouverislandcascadiamodulatedbythebodyandsurfacewavesofthemw86and822012eastindianoceanearthquakes
AT rolandburgmann tectonictremoronvancouverislandcascadiamodulatedbythebodyandsurfacewavesofthemw86and822012eastindianoceanearthquakes
AT vkgahalaut tectonictremoronvancouverislandcascadiamodulatedbythebodyandsurfacewavesofthemw86and822012eastindianoceanearthquakes
AT dipankarsaikia tectonictremoronvancouverislandcascadiamodulatedbythebodyandsurfacewavesofthemw86and822012eastindianoceanearthquakes