Worrying about your own property during an earthquake would be a natural reaction, but what if your home could help in an experiment before an earthquake, to better understand how the ground moves beneath Seattle?
Researchers with the Pacific Northwest Seismic Network are looking for volunteers to help scientists better understand and map the Seattle Basin, described by UW News as a roughly 4-mile-deep area filled with soil and soft rock that makes the urban core especially vulnerable to seismic shaking.
“In our 3D simulations, we see these basins light up with strong shaking, but we need to verify that these basins are shaped the way we think they are,” said Alex Hutko, a PNSN research scientist based at the University of Washington. “We know the basics, but there’s a lot of useful detail that could help us strengthen infrastructure in the right locations.”
While The New Yorker magazine famously gave the shakes to everyone who lives in the Pacific Northwest with a 2015 report on the impending “really big one” and the offshore Cascadia subduction zone, the UW-based team is focused on the sloshing back and forth of seismic waves trapped in soft fill beneath Seattle.
The experiment will watch how seismic waves travel over long distances to figure out the nature of the ground they have traveled through. Urban building codes could be refined through improved mapping of the basin’s overall shape and a better understanding of which neighborhoods experience stronger or weaker shaking.
The UW’s researchers are seeking volunteer sites in which to place six sensitive seismometers, which are about the size of a cooler, use about as much power as a nightlight and take about an hour to install. Hard floors such as basements or garages are required, but tiptoeing around the equipment is not.
The equipment will stay on a site for three to six weeks. The first round of data collection is already happening at Woodland Park Zoo and on other cement floors north of the city’s ship canal. The equipment will be moved to new sites in the first week of June as mapping progresses slightly southward.
“It seems crazy to put very sensitive instruments in the middle of a noisy city,” Paul Bodin, a research professor of Earth and space sciences, told UW News. “Seattle has all kinds of ambient vibrations — traffic, waves on bodies of water, wind blowing on buildings, trains. It’s a situation that most seismologists would run from. But in this case, that noise is providing us with the data.”