Seismic data recorded by the Cascadia Initiative array will be analyzed to look at evolution of the ocean lithosphere from ridge to trench on the Juan de Fuca plate. The determined structure will be related to along-strike variation in down-going plate properties (apparent hydration and whether it occurs in the young and/or older plate, thermal structure, segmentation) and seismic behavior along Cascadia subduction zone. Shear wave structure will be determined from surface waves and ambient noise analysis; receiver functions will indicate the depth distribution of interfaces between contrasting properties. Surface wave results will provide the starting model for the receiver function analysis, which will also use results from the COAST study that documented crustal velocity.
A graduate student will receive training in seismic analysis and Cascadia processes. A portion of the results will provide context for hazard assessment of the margin, in particular along-strike variability. In-depth use of the CI community experiment data will take place and the results of this study is expected underpin a variety of subsequent geoscience investigations.
