Abstract
At periods greater than 1000 seconds, Earth's seismic free oscillations have anomalously large amplitude when referenced to the Harvard Centroid Moment Tensor fault mechanism, which is estimated from 300- to 500-second surface waves. By using more realistic rupture models on a steeper fault derived from seismic body and surface waves, we approximated free oscillation amplitudes with a seismic moment (6.5 × 1022 Newton·meters) that corresponds to a moment magnitude of 9.15. With a rupture duration of 600 seconds, the fault-rupture models represent seismic observations adequately but underpredict geodetic displacements that argue for slow fault motion beneath the Nicobar and Andaman islands.
Original language | English (US) |
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Pages (from-to) | 1139-1144 |
Number of pages | 6 |
Journal | Science |
Volume | 308 |
Issue number | 5725 |
DOIs | |
State | Published - May 20 2005 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- General