Viscoelastic Deformation of the Alaskan Crust and Upper Mantle Subsequent to Regional Earthquakes

Boyd, O.S.
U.S. Geological Survey, Golden, Colorado

Estimates of the probability of earthquakes in Alaska are improved through a finite element, viscoelastic analysis of the evolution of stress in the Earth’s crust and upper mantle.

A solution to the problem is addressed through multiple FEMLAB applications, two for each subdomain, where each subdomain is a fault bounded block. The first application models the elastic response and sets up the boundary conditions for the second application, which models both linear and non-linear viscous behavior. The subdomain applications must exist independently of other subdomain applications such that an earthquake rupture can be specified in which the face of one subdomain has some finite displacement relative to the same face on a neighboring subdomain.

Subdomain independence also allows frictional effects to be explored.