Scotts Mills earthquake

The Scotts Mills earthquake (often referred to locally as the "Spring Break Quake"), which occurred in the U.S. state of Oregon on March 25 1993 at 5:34 a.m. PST, with ML = 5.6, was the largest earthquake in the Pacific Northwest since the Elk Lake and Goat Rocks earthquakes of 1981. The Scotts Mills mainshock epicenter was located at 45.03 N, 122.59 W, about 5 km east of the town of Scotts Mills, and about 54 km south of Portland. Ground motion was widely felt in the Willamette Valley and even the Puget Sound Basin, with felt reports from Roseburg, Oregon, to as far north as Seattle, Washington. The United States Geological Survey reportedcite web
last = Dewey
first = J. W.
authorlink =
coauthors = Reagor, B. G.; Johnson, D. A.; Choy, G. L.; Baldwin, F. W.
title = The Scotts Mills, Oregon, earthquake of March 25, 1993; intensities, strong-motion data, and teleseismic data
work =
publisher = USGS
date = 1994
url = http://pubs.er.usgs.gov/usgspubs/ofr/ofr94163
format =
doi =
accessdate = 2007-01-31 ] that strong motion instruments recorded peak ground accelerations of 0.06 g at Detroit Dam, 44 km to the southeast, and also give an extensive review of damage reports and ground motion intensities. Most structural damage consisted of toppled chimneys and failure of walls of unreinforced masonry. Buildings with damage include Molalla High School and the State Capitol in Salem. The lack of injuries can probably be attributed to the fact that the earthquake occurred in the early morning.

References

External links

* [http://www.ess.washington.edu/SEIS/EQ_Special/ScottsMills/scottsmills.html Scotts Mills Earthquake Summary] from The Pacific Northwest Seismograph Network at Washington State University