Inversions of Teleseismic P-Wave Coda Autocorrelations for Estimating Crustal Structure Below a Floating Ice Platform

Date: 4/26/2019

Time: 06:00 PM

Room: Grand Ballroom

Autocorrelation of teleseismic P-wave coda is an emerging technique for imaging crustal-scale features. The autocorrelation method emphasizes reflections of the incident signal between the free surface and sub-surface seismic discontinuities, in contrast to the P-to-S conversions utilized by the more traditional receiver function method. This distinction is especially relevant for stations sited on floating ice, where high velocity contrasts yield large amplitude reverberations and the intervening water layer decouples teleseismic S-wave energy. We present a workflow for preprocessing and single-station inversion of teleseismic P-wave autocorrelation data recorded on the Ross Ice Shelf during a two-year deployment of 34 broadband seismometers. We show that the three-channel signal-to-noise ratio power spectral densities (i.e., the Fourier transforms of the autocorrelations) can yield accurate estimates of ice and water layer thicknesses. We also present Moho depth estimates from single-station Markov Chain Monte Carlo inversions and compare these values to estimates from continental-scale array methods.

Presenting Author: Michael G. Baker

Authors