Speaker: Harvey Kelsey, Dept of Geology, Cal Poly Humboldt 

Topic: Evidence for recent displacement across the Yaquina Bay fault: new results from luminescence dating and morphology of coastal marine terraces

The Yaquina Bay fault, which runs in roughly an east-west direction through the harbor entrance at Newport, has been recognized as a potentially active fault since the 1990’s. The fault offsets vertically uplifted shorelines, as defined by marine terraces, such that the downtown Newport block is upthrown relative to the southern, South Beach block. In the last few years, new information has been released on this fault because of more advanced dating techniques and also because of the availability of Lidar imaging of the coast that enables more detailed mapping of the marine terraces. The new information confirms the original conclusions about the fault’s characteristics but provides additional insight into faulting in this coastal region. In this talk, I will place the Yaquina Bay fault in the context of the offshore Cascadia subduction zone and I will discuss the present assessment of the fault’s character and degree of activity.