Alaskan Earthquake, 27 March 1964: Vertical Extent of Faulting and Elastic Strain Energy Release

Abstract

The residual displacement field indicates that the primary fault responsible for the great Alaskan earthquake extended to depths of 100 to 200 kilometers and came to within 15 kilometers of the surface. The vertical extent is an order of magnitude greater than reported for all other earthquakes. Approximately 1025 ergs of elastic strain energy was released. About 12,000 aftershocks (ML ≥ 3.5) probably occurred in a 69-day period after the main shock. One-half the strain rebound occurred the first day with the main shock contributing one-fourth of the total.