Mysterious motions along the Pacific Northwest Coast—Investigating Episodic Tremor and Slip

In this lab, students investigate mysterious ground motions along the Pacific Northwest Coast. The investigation begins as students familiarize themselves with the tectonic setting of the Pacific Northwest coastal region . Next, students explore and explain the movement of the Cape Mendocino, CA region that occurred on April 25th, 1992 using data (vector) from high-precision Global Positioning System (GPS) stations and earthquake location data. This case is contrasted with movement recorded by GPS (time-series) in British Columbia from 2004 to 2011. Finally, students investigate a model to explain the GPS time series data for the British Columbia region.

The development of this resources was funded by the National Science Foundation via Award # 0942518

Objectives:

Students will be able to…

  1. Describe the process of Episodic Tremor and Slip and contrast this with the traditional earthquake cycle or Elastic Rebound Theory.
  2. Demonstrate how GPS and seismic observations support our understanding of Episodic Tremor and Slip
  3. Describe the seismic hazard created as the Juan de Fuca plate subducts beneath the North American plate. 

1h
Level: Intermediate

5MB

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