Portland State Magazine Winter 2013

WINTER 2013 PORTLAND STATE MAGAZINE 7 PA R K B L O C K S THE MORRISON BRIDGE lights turned Viking green when the University opened its doors to the community for Portland State of Mind in October. History of Northwest quakes READING CORE SAMPLES of marsh sediment with their trained eyes, Portland State geologists and archeologists were able to determine that four major tsunamis hit the Pacific Northwest coast in the past 1,300 years. Led by geology professor Curt Peterson, the researchers have fresh evidence that earthquake-generated tsunami waves struck Washington’s Olympic Peninsula around 300, 800, 1,100, and 1,300 years ago. The sediment samples were taken in the wetlands between Makah and Neah bays. A layer of clear sand and marine fossils in between layers of dark marsh sediment indicate a tsunami, and radiocarbon testing of the marsh layers date the events. The research was recently published in the Journal of Coastal Research . 