A STANDARD THREE-DIMENSIONAL SEISMIC VELOCITY MODEL FOR SOUTHERN CALIFORNIA

摘要

The southern California earthquake center (scec) has initiated an effort to develop a single standard 3d velocity model of southern California capable of supporting research needs in of strong ground motion simulations, tectonic studies, tomographic imaging, and earthquake location. We describe the development of version 1 of the model and outline the plans for version 2. The model consists of the major populated basins (los angeles basin, ventura basin, san gabriel valley, san feraando valley, and san bernardino valley) embedded in a crust with velocity smoothly varying with depth, over a constant depth mono, and fits a range of geological and geophysical observations. The model is parameterized as a set of objects and rules that are used to generate any 3d mesh of seismic velocity and density values (at length scales appropriate for different uses). This parameterization is convenient to store, transport, and update as new information and verification results become available.