Annual Non-Technical Project Summary for NEHRP Grant Number 1434-95-A-1302


Pacific Northwest Seismograph Network Operations
1434-95-A-1302
S.D. Malone, R.S. Crosson, and A.I. Qamar, P.I.s
Dept. of Earth and Space Sciences, University of Washington
Seattle, WA 98195
Phone:(206)543-8020 FAX:(206)543-0489
e-mail: steve, bob, tony, or ruth@ess.washington.edu

Key words: Seismology, Education-lay, Real-time earthquake information

Oct. 1, 1995 - Sept. 30, 1996

Non-Technical Summary


Operation of the Pacific Northwest Seismograph Network (PNSN) and preliminary analysis of earthquakes in Washington and Oregon continues under this agreement. The PNSN operates 85 stations west of 120 degrees west longitude under this agreement, and 58 additional stations under other support. In addition to network operation, the PNSN conducts an educational outreach program on seismicity and natural hazards. Our web-site is located at: /SEIS/

The PNSN processed 5,041 events between Oct. 1, 1995 and Sept. 30, 1996. Of these, 4,129 were earthquakes or blasts within the network (1,297 of which were too small to locate). Within our network area, 2,288 earthquakes were located west of 120.5 degrees west longitude (including 623 near Mount St. Helens, which has not erupted since 1986), and 140 east of 120.5 degrees west longitude. The remaining events were blasts within the network, regional earthquakes (266) or teleseisms (646). Thirty-two earthquakes were reported felt west of the Cascades in Washington, ranging in magnitude from 2.2 to 5.3, and one earthquake (magnitude 3.1) was felt east of the Cascades.

  • The Duvall Earthquake: The largest earthquake during this reporting period was the magnitude 5.4 Duvall earthquake of 3 May 1997 at 04:04:23 UTC (2 May 1997 at 9:04:23 PM PDT). The epicenter was located at about 7 km depth in the Cascade foothills, about 35 km east-northeast of Seattle and 9 km east-northeast of Duvall. In addition to the mainshock, 22 aftershocks were reported felt. Information on the Duvall earthquake is available through a PNSN Duvall web-page:
    (/SEIS/EQ_Special/Duvall/).

    Back to:... UW Dept. of Earth and Space Sciences ..... SEISMOLOGY INFO..... PNW EARTHQUAKES

    University of Washington Dept. of Earth and Space Sciences, Box 351310 Seattle, WA, 98195-1310
    This is file www.ess.washington.edu/SEIS/PNSN/REPTS/Summaries96/pnsn.nontech.html; modified 3/24/97 - If you see any problems e-mail: seis_web@ess.washington.edu