Center Resources

News from the Information Service

Increased Availability of Strong Motion Records

by D. Tao

Rarely a week goes by when the NCEER Information Service does not receive several requests for strong motion records. Not long ago, obtaining such records was complex and sometimes expensive. However, the initiative and support of many individuals and organizations, combined with the exponential development of the Internet capabilities, have now made it possible for users to obtain digitized records and time histories from the Internet, in some cases without an intermediary. From the NCEER Home Page at , by clicking on the "Accelerograms" bar, users can link to a number of sources for strong motion records, such as the California Division of Mines and Geology (CDMG), the U.S. Geological Survey (USGS), and NCEER's Strongmo database from Lamont-Doherty Earth Observatory.

The following list of sources provides information on obtaining copies of strong motion records from organizations, online systems, or CD-ROM; and assists in finding selected data for an earthquake (date, location, time, site characteristics). Note that the Information Service's intent is to facilitate access to needed ground motion data, not to recommend or select earthquake strong motion records for a particular engineering application.

Additions and comments are welcome concerning both the guide to strong motion records and strong motion resources on the NCEER Home Page. Please contact Dorothy Tao at the NCEER Information Service, University at Buffalo, 304 Capen Hall, Buffalo, NY 14260; phone: (716) 645-3377; fax: (716) 645-3379; e-mail:

Obtaining Strong Motion Records

Accelerograms are available from the organizations, systems, and products listed herein. Records can be obtained directly via on-line systems, as well as in a variety of formats, including magnetic tapes, floppy disks, CD-ROM, or hard copy. It may be necessary to specify selected data such as date, location, time, or site characteristics in order to obtain particular records. The publications listed in this article will help in locating data.

National Geophysical Data Center (NGDC)
325 Broadway
Boulder, CO 80303
Attention: Paula Dunbar
Telephone: (303) 497-6084
Fax: (303) 497-6513

Considered an archive for U.S. and worldwide earthquake data, the NGDC maintains a strong motion archive of over 15,000 worldwide digitized and processed records from 1933-1994. The archive is available on a three-volume CD-ROM set, which represents a broad range of structural and geologic recording environments. Three types of processed records are included on the CDs: uncorrected (raw), corrected (filtered), and response spectra. The Strong Motion CD compilation (Product number 135-A27-001) is available for $452. NGDC also provides customized products and services on tape, diskette, or CD-ROM. While NGDC normally charges for data, if users have data to contribute to NGDC without restriction, they may be able to receive data at no charge. Contact NGDC for additional information.

U.S. Geological Survey (USGS)
Branch of Earthquake and Geomagnetic Information
345 Middlefield Road, MS 977
Menlo Park, CA 94025
Contact: Ron Porcella
Telephone: (209) 456-6140
Fax: (209) 456-6149
Note: Due to reorganization, the above information is temporary

The USGS provides preliminary, uncorrected data from the 1994 Ms 6.7 Northridge, California earthquake from instrumentation in the National Strong Motion Program through anonymous ftp at the Internet address: Data from USGS, Veteran's Affairs, Metropolitan Water District of Southern California, DOE, Army Corps of Engineers, and selected instrumented local structures are included. Refer to READ.ME in the ftp home directory. The USGS also provides strong-motion accelerograms on the CD-ROM Digitized Strong-Motion Accelerograms of North and Central American Earthquakes 1933-1986, by L.C. Seekins, G. Brady, C. Carpenter, and N. Brown, (USGS Digital Data Series DDS-7). Users can download uncorrected strong motion accelerograms from this CD-ROM. Also available is software to correct and process these records, as well as a user's manual. Contact Linda Seekins for more information, phone: (415) 329-5613. To order the CD-ROM, send $32.00 to Map Sales, USGS, Box 25286, Federal Center, Denver, CO 80225.

Lamont-Doherty Earth Observatory of Columbia University
Route 9 West
Palisades, NY 10964
Attention: NoŽl Barstow
Telephone: (914) 365-8477
Fax: (914) 365-8150

Users can access and download on-line parametric and time series data from the Lamont-Doherty/NCEER Strong Motion Database by using Strongmo, an interactive menu-driven computer program. To use Strongmo, it is necessary to obtain NCEER technical report NCEER-90-0024, A User's Guide to Strongmo: Version 1.0 of NCEER's Strong Motion Data Access Tool for PCs and Terminals. The guide is available either through anonymous ftp in directory nceer from the following address: ftp; or from NCEER Publications, report number NCEER-90-0024, $10.00.

Southern California Earthquake Center (SCEC)
SMDB - The Strong Motion Data Base
Institute for Crustal Studies
University of California
Santa Barbara, CA 93106-1100
Contact: Alla Tumarkin
Telephone: (805) 893-8446
Fax: (805) 893-8649

The Strong Motion Data Base (SMDB) provides access to strong motion data, including both parametric and time-series data, for Southern California. The SMDB contains the parameters of 93 earthquakes, 567 stations and 3,182 components, and is continuously updated. This database and its manual are available to users of Sun4 workstations with X-windows via Internet. Shortly SMDB will be accessible from any computer via the Web. For additional information about registration and access, consult the Web Page above and/or Alla Tumarkin.

California Division of Mines and Geology (CDMG)
Strong Motion Instrumentation Program (CSMIP)
801 K Street, MS - 1335
Sacramento, CA 95814
Attention: Robert Darragh
Telephone: (914) 322-3105
Fax: (916) 323-7778

CDMG is a direct source for California data and provides processed data for CDMG stations on paper, tape, or diskette. Processed data from recent events is now available on the Internet, in a directory on ftp or via the URL above.

The Guerrero Accelerograph Network
Seismology Laboratory, UNR
University of Nevada, Reno
Reno, NV 89557
U.S. Contact: John Anderson
Telephone: (702) 784-4265
Fax: (702) 784-1833
URL: (click on Guerrero Accelerograph Network)

Instituto de Ingenieria
Universidad Nacional Autonoma de Mexico
Ciudad Universitaria
Coyoacan 04510, Mexico
Mexican Contact: Roberto Quaas
Telephone: (525) 622-3413
Fax: (525) 616-1514

A joint investigation of the Seismological Laboratory, UNR, and the Instituto de Ingeneria, UNAM, the Guerrero Network consists of 30 digital strong motion accelerographs in Guerrero and neighboring states in Mexico. The Guerrero Strong Motion Network Database provides acceleration records from 1985 to 1995. These records can be accessed through ftp at under directory zeng/GUERRERO or at the Web Page address listed above.

Earthquake and Volcanic Disaster Prevention Laboratory
Kyoshin Net (K-Net)
National Research Institute for Earth Science and Disaster Prevention
3-1, Tennodai
Tsukuba-shi, Ibaraki-ken 305, Japan
Telephone: 0298-54-4940
Fax: 0298-54-4941
URL: (click on K-NET) or for direct access:

The K-NET system provides strong motion data from 1,000 observatories throughout Japan in either UNIX, DOS, or ASCII format, depending on the user's request. Internet users can also search the K-NET database of strong-motion records and site information. For additional information about requests, searching, and access, consult the Web Page listed above.

Helpful Publications

The following publications are useful in locating selected data for an earthquake, such as date, location, time, site characteristics, and other parameters.

Dunbar, Paula K., Lockridge, Patricia A. and Whiteside, Lowell S., Catalog of Significant Earthquakes, 2150 BC to 1991 AD, Boulder, CO, National Geophysical Data Center, September 1992. Available for $46 including diskette (add $10 for international orders) from National Geophysical Data Center, NOAA, Code E/GC4, Dept. ORD, 325 Broadway, Boulder, CO 80303-3328.

This catalog lists historic earthquakes that have occurred worldwide from 2150 BC to 1991 AD. The entries include all events that meet at least one of the following criteria: damage of approximately $1 million or more; more than ten deaths; magnitude > 7.5; and intensity > X (for events lacking magnitude). The following seismological parameters are given: date and time of event; epicenter location; depth; magnitude; intensity; deaths; damage (in U.S. dollars); related tsunamis; and geographic location. Earthquakes are first listed chronologically and then alphabetically by country or region. An enclosed diskette contains the catalog in ASCII format. The catalog is also downloadable from the NGDC Web Page, and is included in the Seismicity Catalog CD-ROM Collection ($137), a two volume CD collection that contains data for more than four million earthquakes dating from 2100 BC to 1995 AD. Contact NGDC for order information.

Leeds, David J., Recommended Accelerograms for Earthquake Ground Motions, Vicksburg, MS, U.S. Army Engineers Waterways Experiment Station, 1992. (State-of-the-Art for Assessing Earthquake Hazards in the United States Report 28). Available for $52.00 from the National Technical Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161.

This publication lists recommended worldwide accelerograms and response spectra to accompany all representative values for Richter magnitudes at distance-determined peak horizontal accelerations-velocities-durations, hard and soft sites, shallow and deep earthquakes. The motions shown are useful where dynamic analyses are contemplated and where time histories (and response spectra) are required that approximate the effects of earthquakes as they would be felt in the free field at the engineering site.

Stover, Carl W. and Coffman, Jerry L., Seismicity of the United States, 1568-1989 (Revised), Washington, DC, U.S. Government Printing Office, 1993. (USGS Professional Paper 1527). Available for $26 from Book and Open File Report Sales, U.S. Geological Survey, Federal Center, Box 25286, Denver, CO 80225.

This publication describes principal earthquakes (MMI ?VI or Richter magnitude ? 4.5) that occurred in the U.S. from 1568-1989. Organized by state, the publication contains tabular listings that include date, location, magnitude, intensity, and references for principal earthquakes in 47 states. Following each table are brief narratives of the damaging effects of earthquakes of intensity ?VI.

Click here to return to the Table of Contents

| Home | NCEER | Information Assistance | Publications | Databases, Software |
| Events | New! | Links | Data Resources |