Poster illustrates the violence of ground shaking expected for three kinds of earthquakes: (1) Cascadia subduction zone great earthquake; (2) “deep” earthquake within subducting Juan de Fuca Plate beneath Pacific Northwest (e.g. Nisqually 2001); and (3) local magnitude 7 earthquake on Portland Hills Fault.
Relative earthquake hazard maps compare the expected violence of earthquake ground shaking and likely damage over a map area produced by a generic earthquake outside of the mapped region. Relative earthquake hazard maps are usually a combination of several different earthquake risks added together. For example, the Oregon Department of Geology and Mineral Industries (DOGAMI) constructed relative earthquake hazard maps for regions in Oregon by combining slope instability (landslide), amplification of ground shaking by weak near-surface geology, and liquefaction potential into one map. Areas of particularly high earthquake risk are mapped as “red zones” often because of high liquefaction potential near waterways (rivers and lakes) or because of large thickness of weak near-surface geologic layers such as unconsolidated sediments. This classroom activity combines three related activities into one: a slope instability demonstration; a ground amplification demonstration; and a liquefaction experiment.
This QuickTime animation shows how P, S, and surface seismic waves are amplified as they pass from strong bedrock areas to areas underlain by weaker layers of rocks and sediment. In loose water-saturated sediment, liquefaction can occur causing the ground to turn to “quick sand” during earthquake shaking. Animation is narrated to explain the events occurring during the animation.
The morning hike up Kautz Creek to examine debris flows.
Pat Pringle (Centralia Community College) was our expert guide on the Mt Rainier Rainier field trip.
Following the volcano evacuation route away from Orting High School.
Enjoying the sun while discussing the debris flow along the Nisqually River Valley.
Upper Nisqually River Valley leading to the Nisqually glacier at its headwaters.
Field trippers catching up on much needed rest after long day in the field.
The canoe launching operation at Copalis Beach, Washington on the shore of the Copalis River.
(Photo by Juliet Dowsett)
Irene Catlin and Shelli Colwell preparing to launch.
(Photo by Juliet Dowsett)
Roger Groom (back to camera) directing the canoe landing and parking operation.
Bob Filson and the “lahars” team at Copalis ghost forest. The lahar team motto was “We’ve got you covered.”
David Yamaguchi explaining the history and process of tree-ring dating of the Copalis Ghost forest.
Juliet Dowsett in the fashion of the day with Copalis ghost forest in background.
The Tsunami team with James Davies at the head of the line and team leader Peter Ritson on the left.
Ken Austin describes the installation and operation of the Plate Boundary Observatory (PBO) GPS receiver at Elma, Washington.
Pointing in the northeast direction that the Elma PBO station is being pushed by the Juan de Fuca Plate.
Beth Pratt-Sitaula introduces teachers to TOTLE digital resources.
Exploring resonance during earthquake shaking through the kid-friendly version of the BOSS model.
Adding shear resistance to a model building frame using gussets, shear walls, and cross members.
Beth Norman, Pierce College, leads the Lahars as they report classroom implementation plans.