JOYCE — Paleo-tsunamis, or tsunamis occurring prior to the historical record or for which there are no written observations, will be covered in an evening presentation and daytime field trip today and Saturday.
Both events are free and open to the public.
“Paleo-tsunamis in the Strait of Juan de Fuca,” a presentation by Sarah Sterling of Portland (Ore.) State University, with contributions by Ian Hutchinson of and Curt Peterson of Portland State, will be held at the Crescent Grange, 50870 state Highway 112, at 6:30 p.m. tonight.
Workshops
A field workshop including sessions such as “Birds with Barb,” “Tsunamis with Sarah” and “Nearshore Overview/Fish with Anne,” will be held from 8:30 a.m. to 2 p.m. Saturday.
The field workshop will meet at the Salt Creek county access parking lot
At the evening lecture, the presenters will discuss how tsunamis are identified in the field and through diatom analysis, as well as how time frames are established for those identified events through radiocarbon dating.
It will delve into the general impact of the events and how correlation of those events from locations along the coast of the Strait of Juan de Fuca helps refine the picture of tectonic mechanisms that generate Cascadia subduction zone earthquakes.
The field workshop will begin with a quick discussion on the overall function of the Salt Creek nearshore and a coastal and estuary bird walk led by Barb Blackie Peninsula College and Western Washington University.
Attendees will then visit Salt Creek Marsh to discuss with Sterling why this location is a good setting for studying paleo-tsunamis and how evidence of past seismic events is collected.
Strategies and techniques used for collecting radiocarbon and diatom samples also will be discussed.
The field workshop will wrap with a quick beach seine in the lower main channel of the river and a discussion on fish use of the nearshore with Anne Shaffer of the Coastal Watershed Institute.
For more information, email Shaffer at anne.shaffer@coastalwatershedinstitute.org or Nicole Harris at nicole.harris@coastalwatershedinstitute.org.