title: Earth's free oscillations excited by the 26 December 2004 Sumatra-Andaman earthquake.
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 x 10(22) 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.
authors.affiliation: Department of Geology and Geophysics, Yale University, Post Office Box 208109, New Haven, CT 06520-8109, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Park
authors.forename: Teh-Ru Alex
authors.initials: TR
authors.lastname: Song
authors.forename: Jeroen
authors.initials: J
authors.lastname: Tromp
authors.forename: Emile
authors.initials: E
authors.lastname: Okal
authors.forename: Seth
authors.initials: S
authors.lastname: Stein
authors.forename: Genevieve
authors.initials: G
authors.lastname: Roult
authors.forename: Eric
authors.initials: E
authors.lastname: Clevede
authors.forename: Gabi
authors.initials: G
authors.lastname: Laske
authors.forename: Hiroo
authors.initials: H
authors.lastname: Kanamori
authors.forename: Peter
authors.initials: P
authors.lastname: Davis
authors.forename: Jon
authors.initials: J
authors.lastname: Berger
authors.forename: Carla
authors.initials: C
authors.lastname: Braitenberg
authors.forename: Michel
authors.initials: M
authors.lastname: Van Camp
authors.forename: Xiang'e
authors.initials: X
authors.lastname: Lei
authors.forename: Heping
authors.initials: H
authors.lastname: Sun
authors.forename: Houze
authors.initials: H
authors.lastname: Xu
authors.forename: Severine
authors.initials: S
authors.lastname: Rosat