TERRAscope and CUBE Project at Caltech

Abstract

The TERRAscope project of the California Institute of Technology began in 1988 and now has six very broadband seismic stations (PAS, GSC, PFO, SBC, ISA, and SVD) in southern California (Figure 1). The goal of TERRAscope is to provide high-quality broadband data needed for significant advances in both regional and global seismology. TERRAscope will replace the old Caltech seismographic network in southern California, which dates back to the 1920s. In many cases, new stations are deployed in cooperation with local institutions. The goal is to encourage involvement of both students and researchers in the operation of the stations and analysis of new data. The station PAS is a joint project between Caltech, the University of Southern California, the U.S. Geological Survey (USGS), and the Incorporated Research Institutions for Seismology (IRIS). The station SBC was deployed in cooperation with the University of California at Santa Barbara. The station PFO is operated jointly with the University of California at San Diego, and the station SVD was installed and is operated by the USGS. Except for SVD, all of the stations are equipped with a broadband Streckeisen STS-1 seismometer and Quanterra data logger with a 24-bit digitizer and a Kinemetrics FBA-23 strong-motion sensor. The station SVD has a Streckeisen STS-2 seismometer and a Guralp CMG-5 accelerograph. The project is funded mainly by grants from the L. K. Whittier Foundation and the Arco Foundation. In addition to the automatic dial-up data retrieving system called Caltech Gopher (adapted from the IRIS Gopher system) has been implemented. The Caltech Gopher receives mail from NEIC for teleseisms and the SCSN with origin time, location, and magnitude for regional events. The Gopher retrieves data from all six TERRAscope stations for these events. The TERRAscope data reside in an FTP anonymous account (seismo.gps.caltech.edu; password: “your e-mail address”) at the Caltech Seismological Laboratory, and are available to users through Internet. Usually the data are available within 30 minutes after a regional event and several hours after a teleseism. In the near future a new version of the Gopher software will be installed, which will also make some of the Gopher data available directly from the IRIS-DMC Gopher. When the Data Center of the Southern California Earthquake Center begins full operation in early 1992, it will take over the distribution of earthquake data from southern California, including both TERRAscope Gopher data and continuous data from the tape cartridges. The data will also be available from IRIS-DMC, and future improvements and changes in data access will be posted on the IRIS-DMC bulletin board.