UW News

August 19, 2002

MEDIA ADVISORY: News conference at trench exposing Seattle fault

News and Information

** WHAT: News conference featuring an exposed section of the Seattle fault zone
** WHO: Brian Sherrod of the United States Geological Survey and other scientists from the USGS and the University of Washington
** WHEN: 10 a.m. Wednesday, Aug. 21
** WHERE: At the site of the trench, near Vasa Park in Bellevue (see directions below)

DETAILS: An excavation by Sherrod in the Vasa Park area of Bellevue has exposed evidence for a past surface rupture along the Seattle fault zone. The excavation exposes glacial deposits at one end of the trench and 9 million- to 10 million-year-old bedrock and older glacial deposits at the other end. The contact between the older deposits and the younger deposits is a fault. Movement on this fault pushed the older deposits up and over the former land surface, seen in the trench as a buried organic soil layer up to 11,500 years old. The find shows that earthquakes and surface rupture previously occurred in the Bellevue area and still pose a hazard.

DIRECTIONS: From eastbound Interstate 90, take exit 11A (marked for 150th Avenue Southeast/156th Avenue Southeast/Southeast 37th Street) toward Southeast 37th Street. Where the ramp splits, stay to the right. From the two lanes that go right, stay in the left lane. Cross 150th Avenue Southeast, staying on Southeast 37th Street through the first light. Where the street again splits in a Y, stay left and go through the tunnel under I-90. Continue down the hill (the street becomes Southeast 35th Street) and then take the first right onto 164th Place Southeast. The site is a short distance ahead on the right, just beyond the Eastside Christian Church. Yellow caution tape is strung around the excavation.


For more information, contact Bill Steele in the UW seismology laboratory, (206) 685-2255.