© Kelsey et al./USGSThis LiDAR image (acquired in 2006 by the USGS) shows five paleoseismic study sites (red dots with block perimeters) and three Holocene faults (solid red lines) inferred from the data.
Tectonically speaking, there's a lot going on in the Pacific Northwest. From the Cascadia subduction zone, where the Juan de Fuca tectonic plate is slowly pushing its way underneath the North American plate, to the Seattle Fault, where Native American legends recorded a massive earthquake 1,100 years ago, the region has its fair share of seismic hazards.
Now add to that three more
potentially dangerous faults in the Bellingham Basin, a tectonically active area along the coast of Washington, near the Canadian border.
A team of researchers has discovered active tectonic faults in this region nearly 40 miles (60 kilometers) north of any previously known faults.
"We've known for a long time that the whole
Pacific Northwest region is contracting very slowly north-to-south, at the rate of a few millimeters per year," said Richard Blakely, a geologist with the U.S. Geological Survey in Menlo Park, Calif., who was part of the study.
"It doesn't sound like very much, but when you concentrate that contraction on specific faults, they can become rather dangerous."