Computation of deformation induced by earthquakes in a multi-layered elastic crust -: FORTRAN programs EDGRN/EDCMP

This is the first article in a series in which we introduce methods to determine the permanent and transient deformation induced by earthquakes or similar sources. The point-like and extended foci can be located in a stratified elastic half-space. The software includes a tool to combine the sources to one or more extended sources with arbitrary strike and dip. The number of layers is essentially not limited. The output covers surface and subsurface displacements, strain, tilt and stress. Several effective techniques have been used to solve the stability and convergence problems in computation of the Green's functions, so that the programs are small, fast and accurate. To control the accuracy of the numerical results, the software provides an optional link to Okada's analytical solutions in the special case of a homogeneous half-space. This can also be used for creating zeroth order approaches, i.e. starting models. (C) 2002 Elsevier Science Ltd. All rights reserved.