Exciting news! We're transitioning to the Statewide California Earthquake Center. Our new website is under construction, but we'll continue using this website for SCEC business in the meantime. We're also archiving the Southern Center site to preserve its rich history. A new and improved platform is coming soon!

Southern California Earthquake Center Strong Motion Database SMDB

A. A. Tumarkin, Ralph J. Archuleta, & Alexei G. Tumarkin

Published 1994, SCEC Contribution #191

SMDB was designed to provide a fast and easy access to the strong-motion data. SMDB and its manual (the SMDB User's Guide) are available for the users of Sun 4 workstations with X-windows via Internet.

The database combines the following features:
• it has a menu-driven user-friendly interface;
• both parametric and time-series data are available from the database;
• the parametric data are accessed through the network database model;
• the time-series are stored on-line in SAC (Seismic Analysis Code by LLNL) format.

The major possibilities of the database include:
• performing various types of queries;
• processing time-series by means of SAC;
• obtaining maps of events and stations.

For example, to access accelerograms with peak acceleration greater than 100 cm/s2 recorded at an epicentral distance between 20 and 50 km at alluvial sites, a user would enter:

st where peak_acc>100 and epi_dist between 20 and 50 and s.geology like "*alluvium*"

(st stands for "select traces") either by typing directly from the keyboard or by
clicking on the appropriate menu items. The selected time-series can then be
analyzed using SAC within the SMDB environment.

The SMDB database now contains the information about 85 earthquakes, 374 stations and 1911 components, including records of the 1992 Cape Mendocino and Landers earthquakes. The performance of SMDB will be demonstrated on a stand-alone SUN computer.

Tumarkin, A., Archuleta, R. J., & Tumarkin, A. G. (1994). Southern California Earthquake Center Strong Motion Database SMDB. Oral Presentation at 89th Annual Meeting, Seismological Society of America. doi: 10.1785/gssrl.65-1-15.