New research led by the University of Arizona and published in the journal Science Advances shows a seismic event around 1100 years ago likely involved faults rupturing together or back-to-back earthquakes in western Washington. Scientists examined tree rings from six sites, finding they had similar growth patterns and died in the same time span. The University of Washington's Harold Tobin, director of the Pacific Northwest Seismic Network, says it's exciting and notable research. "We knew about the Seattle Fault, the Tacoma Fault, Saddle Mountain, Southern Whidbey Island- the whole range of these fault lines in our area that have the potential for earthquakes," Tobin said. "What we have not seen is any evidence of them interacting with each other in this way- linking up to create one larger, up to magnitude 7.8 earthquake, or a series of smaller but still big, damaging earthquakes." Read the full story here: https://www.king5.com/article/tech/science/environment/research-uncovers-new-details-earthquake-threats-western-washington-university-of-arizona/281-c8a32912-a1ce-4dc4-8ead-6c0b49922d7b