Effects of the 2004 Sumatra Earthquake on Earth Rotation: A Comparison Between Theory and Observations

摘要

On 26 December 2004, a large earthquake shook northern Sumatra, Indonesia, and then shook the whole of humanity by causing probably the deadliest tsunami in recorded history. Conservation of angular momentum, a fundamental principle of physics, indicates that the earthquake also had an effect on Earth rotation. Current theory estimates that this event shifted the mean pole approximately 2.5cm in the direction of 145 degrees E and decreased the length of day by 2.68 microseconds. This study compares these theoretical results to observation-based estimates of the Earth orientation parameters (EOP).