thumbnail

Mantle structure beneath the western edge of the Colorado Plateau

Geophysical Research Letters

By:
, , , , , ,
DOI: 10.1029/2008GL033391

Links

Abstract

Teleseismic traveltime data are inverted for mantle Vp and Vs variations beneath a 1400 km long line of broadband seismometers extending from eastern New Mexico to western Utah. The model spans 600 km beneath the moho with resolution of ???50 km. Inversions show a sharp, large-magnitude velocity contrast across the Colorado Plateau-Great Basin transition extending ???200 km below the crust. Also imaged is a fast anomaly 300 to 600 km beneath the NW portion of the array. Very slow velocities beneath the Great Basin imply partial melting and/or anomalously wet mantle. We propose that the sharp contrast in mantle velocities across the western edge of the Plateau corresponds to differential lithospheric modification, during and following Farallon subduction, across a boundary defining the western extent of unmodified Proterozoic mantle lithosphere. The deep fast anomaly corresponds to thickened Farallon plate or detached continental lithosphere at transition zone depths. Copyright 2008 by the American Geophysical Union.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Mantle structure beneath the western edge of the Colorado Plateau
Series title:
Geophysical Research Letters
DOI:
10.1029/2008GL033391
Volume
35
Issue:
10
Year Published:
2008
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article