VANCOUVER, Wash. -- Scientists with the U.S. Geological Survey are studying the seismic signature from the Oso landslide in an effort to create a better warning system for future slides.
The work is happening at the Cascades Volcano Observatory, because landslides usually accompany volcanic eruptions.
Mount Rainier has long been considered the most dangerous volcano in North America, not just for its massive size, but the fact that it's so close to a major population center. Landslides and lahars, the rush of rapidly melting glaciers off the top of the mountain, could race down drainages and into river valleys around the mountain.
Cities like Orting would get about an hour notice, said Scott Heinze, Deputy Director of Pierce County Emergency Management. And in about 90 minutes, a rush of mud and melted ice would go down the Puyallup River and reach the Port of Tacoma and Puget Sound.
Warning systems on Mount Rainier now rely on instruments looking for unusual flows of water and debris, and trip wires to set off alarms. A series of hazard warning sirens and speakers are located in Orting, Puyallup and other vulnerable cities. More time, more warning could mean thousands of lives potentially.
CVO is looking at whether the initial vibration given off by a large movement of dirt and ice could give more warning. In the Oso slide, estimated at three times the weight of the largest of Egypt's pyramids, the seismic signal started less suddenly than an earthquake, which is typically seen as a abrupt slip as it releases energy.
Kate Allstadt, a researcher at CVO, was with the Pacific Northwest Seismic Network at the University of Washington during the Oso slide in March 2014.
"This is a really well recorded event, and we have a lot of information about it," said Kate Allstadt a Researcher at CVO. "Trying to detect these landslides as soon as they happen, using seismic methods and increasing the warning times for people down slope."