<i>Ps-P</i> Tomography of a Midcrustal Magma Reservoir Beneath Cleveland Volcano, Alaska

Portner, Daniel Evan; Wagner, Lara S.; Janiszewski, Helen A.; Roman, Diana C.; Power, John A.
2020
GEOPHYSICAL RESEARCH LETTERS
DOI
10.1029/2020GL090406
Seismic tomography of the crust is an essential tool for studying the three-dimensional structure of magmatic plumbing systems feeding active volcanoes, but it is often limited in resolution by the absence of deep local seismicity. Teleseismic receiver functions can be used to illuminate local structural variations, but typically do not account for the effects of three-dimensional velocity heterogeneities. Here we harness the complementary strengths of both techniques by processing Ps-P delay times derived from teleseismic receiver functions in a tomographic S wave inversion. Using our inversion technique, we produce the first tomographic crustal velocity model beneath Cleveland Volcano, identifying a vertically extensive high V-P/V-S anomaly beneath the volcano that likely signifies a middle-to-lower crustal magma reservoir. The observation is the first of its kind in the central Aleutians, illustrating the potential of our technique to advance our understanding of crustal magmatic systems without broad seismic networks or distributed local seismicity.