Upper mantle structure from teleseismic P wave arrivals in Washington and northern Oregon
Links
- More information: Publisher Index Page (via DOI)
- Download citation as: RIS | Dublin Core
Abstract
Teleseismic P wave travel time residuals are used to detect lateral velocity heterogeneities in the upper mantle beneath Washington and northern Oregon. The results of an inversion for three-dimensional velocity variations resolves an east dipping high-velocity zone that we interpret as the subducting Juan de Fuca plate. The plate is characterized by 3–8% higher velocities than those in the surrounding upper mantle. Inversion of the travel time data and ray trace modeling indicate that the plate extends to a depth of 200–300 km. The plate dips at a moderate angle of 45° to the east-northeast beneath the central Washington Cascade Range north of Mount Rainier, with 5% faster velocities than the surrounding upper mantle. Beneath the North Cascade Range of Washington, the plate strikes to the northwest and has 6–8% faster velocities than the upper mantle to the west. South of 47°N, beneath the Cascade Range in southern Washington and northern Oregon, the plate dips steeply to the east and has 3–4% faster velocities than the surrounding upper mantle. Based on changes in the geometry and velocity structure of the subducted Juan de Fuca plate east of about 123°W, we propose that the subducted slab is segmented into three sections beneath Washington and northern Oregon.
Publication type | Article |
---|---|
Publication Subtype | Journal Article |
Title | Upper mantle structure from teleseismic P wave arrivals in Washington and northern Oregon |
Series title | Journal of Geophysical Research Solid Earth |
DOI | 10.1029/JB091iB02p02077 |
Volume | 91 |
Issue | B2 |
Year Published | 1986 |
Language | English |
Publisher | American Geophysical Union |
Description | 18 p. |
First page | 2077 |
Last page | 2094 |
Google Analytic Metrics | Metrics page |