Advancing Ocean, Retreating Bluffs around Port Townsend

Quimper Geological Society is hosting a free lecture by Paul Loubere, a retired research professor who will provide his insights about shoreline bluff retreat and the resulting sediment dispersal. Shoreline bluffs around Port Townsend, Indian Island and Marrowstone Island are actively eroding and raise key questions such as: what is the rate of erosion at a given locality, what factors affect that rate, and where is the sediment shed by the bluffs going? Paul’s data is based on calculating broad bluff retreat rates over the past 150 years from examination of historical maps and aerial photos compared to modern satellite images. Paul’s will also describe the geologic composition of the bluff layers and what the mapping of the seabed in Port Townsend Bay reveals about slope failures.