PNSN Strong Motion Network PNSN > Strong Motion > Overview

5. Status Report, August 14, 2002

The strong-motion subnetwork began in 1996 with the installation of 3 high-dynamic range, digital instruments. The models selected were the IDS-24 manufacured by Terra Technologies of Redmond, Washington. These instruments successfully recorded on-scale waveform data from regional earthquakes such as the the M=4.9 Bremerton earthquake of June 23, 1997.

The PNSN is now operating 80 strong motion seismographs in the Pacific Northwest. All but 4 stations have real time telmetery. Forty of these stations are ANSS stations, where 20 were installed in FY2000 and another 20 in FY2001. All 40 seismographs of the ANSS stations are the Kinemetrics K2. Many additional stations are also K2s. Five of the ANSS stations have L4 short period sensors digitized by the K2. All ANSS stations use the Internet for real time telemetry.

Fifteen stations are CREST stations. These have both Guralp broadband velocity seismometers as well as Kinemetrics Episensor strong motion sensors (except for station LTY) and are digitized by Reftek digitizers. The CREST stations use a hybrid of dedicated phone lines and the Internet for data telemetry.

FY2002 marks the first year of non-federal funding for strong motion instrumentation. The Oregon Department of Geology and Mineral Industries purchased 3 Kinemetrics K2s. Two seismographs were installed south of Portland by the PNSN and one was installed in Bend by the University of Oregon.

A significant accomplishment of the strong motion network was the successful recording of the Mw = 6.8 February 28, 2001 Nisqually earthquake. PNSN strong motion seismographs provided 100 % data recovery on the 46 stations that were currently deployed. Sources of data and information on the Nisqually earthquake are listed on the Strong Motion Home Page. Data from strong motion seismographs are routinely utilized in ShakeMap.

Station locations, sensor types, and telemetry are summarized in a station list.

Time series from all PNSN stations, including the strong motion stations, are archived on a quarterly basis at IRIS. These time series data, as well as station response information, are available through automated request methods.

Questions about the strong motion program can be directed to: George Thomas, 206-685-7099, george@ess.washington.edu

Updated August 14, 2002