THE SOUTHERN CALIFORNIA EARTHQUAKE CENTER FAULT INFORMATION SYSTEM

The Southern California Earthquake Center’s Fault Information System (FIS) provides fault-related data and models from multiple databases and datasets by use of code, metadata and Web interfaces. Using emerging Web services technology, which enables queries and data interchange irrespective of computer software or platform, the first generation FIS may be searched and downloaded live, by automated processes, as well as interactively, by humans using a browser. Users get data in ascii tables or encoded in XML. We are also testing the effectiveness of querying multiple databases via a fault database ontology and the ontology query language RDQL. For over a decade, the California Geological Survey (CGS), SCEC, and the U. S. Geological Survey (USGS) have put considerable, shared resources into compiling and assessing published fault data, then providing the data on the Web. Several databases now exist, with different formats, datasets, purposes, and users, in various stages of completion: a compilation of consensus values used to construct the USGS and CGS national and state probabilistic seismic hazard maps (Peterson and others, 1996 & 2002); the southern California paleoseismic database of Hecker and others (1998); and the USGS National Quaternary Fault and Fold database (Machette and Haller, 2002). When fault databases were first envisioned, the full power of today's internet was not yet recognized, and the databases became the Web equivalents of review papers, where one could read an overview summation of a fault, then copy and paste pertinent data. Numerous researchers today also require rapid queries and downloads of data. Consequently, the first component of the FIS is a MySQL database that delivers numeric data from the fault databases. In addition, over the next year, the FIS will also forge the first interfaces with model parameters and 3-D fault representations of SCEC’s Community Fault Model (CFM). CFM is developing a Postgresql database of parameters used in its model, and also provides text files needed to construct the triangulated surfaces of its 3-D fault representations. Finally, over the next year the FIS will make available the visualizations of the SCEC IT Intern team, whose LA-3D uses Java3D to create images of southern California’s earthquakes, and faults of both the CGS and CFM models. http://epicenter.usc.edu/fisweb/