Scientists seek homes in the Seattle area in which to install quake monitors

Published 17 December 2009

Scientists want to install seismic monitors in homes in the Seattle area to measure ground-shaking; with detailed information on the way the ground shakes in a particular spot, it may be possible to design buildings tailored to their exact locations; the instruments also will help construct “shake-maps” to pinpoint areas of heaviest damage after major earthquakes

Would you share your home with a seismograph? If so, you may be able to help study Northwest earthquakes. Researchers at the University of Washington and the U.S. Geological Survey are seeking strategically located homes and other buildings in the Seattle area where they can install instruments that measure ground-shaking.

Seattle Times’sSandi Doughton writes that the NetQuakes program will start with twenty citizen scientists and expand soon to forty, said Steve Malone, of the UW’s Pacific Seismic Network. Within a few years, scientists hope the network will include 500 instruments.

The additional data will help identify areas that are most vulnerable to earthquake damage, and aid in the design of quake-resistant structures, Malone said. With detailed information on the way the ground shakes in a particular spot, it may even be possible eventually to design buildings tailored to their exact locations. The instruments also will help construct “shake-maps” to pinpoint areas of heaviest damage after major earthquakes.

A similar program is under way in the San Francisco area, where volunteers are hosting sixty-eight instruments.

Unlike traditional seismometers, which can detect tiny ground motions across long distances, the NetQuakes instruments are designed to measure strong shaking close to an earthquake source.

Doughton notes that the Puget Sound area is laced with geologic faults, making it one of the U.S.’s top earthquake hot spots. The Pacific Northwest also is menaced by possible mega-quakes from the Cascadia subduction zone along the coast.

During an earthquake, the amount of shaking in the Seattle area varies greatly based on geology, soil type, and other variables that scientists are still trying to understand, Malone said. A dense network of instruments will help reveal those patterns. There now are about 100 strong-motion detectors in Washington and Oregon, with about 50 situated along the Puget Sound corridor.

The scientists are targeting the new instruments to areas without coverage and places that could be vulnerable during earthquakes. For example, they would like one near the east end of the I-90 bridge, where soft soils are likely to shake strongly.

The ideal site is a one- or two-story building less than 4,000 square feet, without a deep basement, and located on a quiet street within a half-mile of a business district. Buildings must have electrical power and Internet access, either wired or wireless, and a concrete floor near street level where the instrument can be bolted down. The seismographs consume only about 25 cents worth of power a month and take up a minuscule amount of computer bandwidth. “There should be little impact on anyone who hosts one of these,” Malone said. “But the value could be very high.”