Related Experiment Video
Updated: Jul 11, 2026

Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior
Published on: April 13, 2016
Earth's free oscillations excited by the 26 December 2004 Sumatra-Andaman earthquake
Jeffrey Park1, Teh-Ru Alex Song, Jeroen Tromp
1Department of Geology and Geophysics, Yale University, Post Office Box 208109, New Haven, CT 06520-8109, USA.
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.
More Related Videos
Related Concept Videos
Acceleration due to Gravity on Earth
The acceleration of an object close to the Earth, because of the Earth's gravitational pull, is called the acceleration due to gravity. It is always directed...
Variation in Acceleration due to Gravity near the Earth's Surface
The difference between the true and apparent weights is proportional to the square of the Earth's angular speed. Since the...
Tidal Forces
Measuring Acceleration Due to Gravity
A simple pendulum can be described as a point mass and a string. Meanwhile, a physical pendulum is any object whose oscillations are similar to a simple pendulum, but cannot be modeled as a point mass on a string because its mass is distributed over a larger area. The behavior of a physical pendulum can be modeled using the principles of...
Acceleration due to Gravity on Earth
Geoid and Ellipsoid

