Kinematics of the Great 2004 Sumatra-Andaman Earthquake from ...


Nov 14, 2013 (4 years and 5 months ago)


Kinematics of the Great 2004 Sumatra
Andaman Earthquake from GPS static offsets

Paramesh Banerjee


The Great 26 December 2004 Tsunami
producing Sumatra
Andaman earthquake caused
a large area of earth’s surface to shrink leading to change in shap
e and size of the earth.
This instantaneous coseismic visco
elastic response of the upper lithosphere to tectonic
plate adjustment process, were picked up by a large number of Continuously operating
GPS stations at distances of upto 4500km from the epicent
er. Using GPS measured
coseismic static offsets, we estimated energy release of the mega
earthquake equivalent
to a magnitude of Mw 9.2, and led up to detailed modelling of the kinematics of the
rupture process. Further analysis of the post
seismic GPS dat
a indicated

in favour of a
vigorous viscoelastic relaxation involving both upper and lower mantle. Following the
2004 event, it was possible to predict that the Coulomb Failure Stress increased by about
0.25 bar in the region of future hypocentral zone of
March 2005 Nias earthquake.