For details of this project, see this article. An interpretation of mantle xenoliths in light of these results is found here.
Using a small array of permanent (black) and portable (red) seismographs, we recorded teleseismic (distant) earthquakes from July, 1995 through July, 1996. P-wave arrival times were determined using multi-channel cross-correlation.
Azimuthal variations in station residuals indicate substantial variations in upper-mantle velocity structure. We inverted the travel-time residuals using a 3-D tomography code developed by John VanDecar.
A checkerboard resolution test revealed the limitations of the model's resolution.
In addition to the high-velocity edge of the Alaskan slab (blue), the model reveals a substantial low-velocity model beneath the northern Cordillera (red), which we interpret as a mantle upwelling driven by the opening of a slab window and the retreat of the slab edge.
Go back.Andrew Frederiksen / firstname.lastname@example.org