HUSCAP logo Hokkaido Univ. logo

Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Science / Faculty of Science >
Peer-reviewed Journal Articles, etc >

Long- and short-term postseismic gravity changes of megathrust earthquakes from satellite gravimetry

Files in This Item:
GRL_41_5451-.pdf798.05 kBPDFView/Open
Please use this identifier to cite or link to this item:

Title: Long- and short-term postseismic gravity changes of megathrust earthquakes from satellite gravimetry
Authors: Tanaka, Yusaku Browse this author
Heki, Kosuke Browse this author →KAKEN DB
Keywords: postseismic gravity changes
viscoelastic relaxation
seismic cycle
subduction zone
Issue Date: 16-Aug-2014
Publisher: American Geophysical Union
Journal Title: Geophysical Research Letters
Volume: 41
Issue: 15
Start Page: 5451
End Page: 5456
Publisher DOI: 10.1002/2014GL060559
Abstract: Using monthly satellite gravimetry data, we studied time-variable gravity field after three M9 class earthquakes, the 2004 Sumatra-Andaman, 2010 Chile (Maule), and 2011 Tohoku-oki earthquakes. The observations showed that the gravity typically (1) decreases coseismically, (2) continues to decrease for a few months, and (3) increases over a longer period. Therefore, postseismic gravity changes have two components with different time constants and polarities. The mechanisms of short- and long-term postseismic gravity changes are not as clear as coseismic changes at the moment, but might be explained to some extent with afterslip and the Maxwell viscoelasticity, respectively. These two components are difficult to discriminate with surface velocity measurements because the forearc area moves trenchward at both stages. They appear in different polarities in gravity, making satellite gravimetry a unique tool to separate them.
Rights: Copyright 2014 American Geophysical Union.
Type: article
Appears in Collections:理学院・理学研究院 (Graduate School of Science / Faculty of Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)

Submitter: 日置 幸介

Export metadata:

OAI-PMH ( junii2 , jpcoar_1.0 )

MathJax is now OFF:


 - Hokkaido University