Attenuation of ice-sheet reverberations in teleseismic P-wave receiver functions
Creators
- 1. Velseis Pty Ltd and The University of Queensland
- 2. Velseis Pty Ltd
Description
Teleseismic P-wave receiver functions (PRFs) in ice-covered regions are contaminated by reverberations within the ice-sheet. The crustal conversion events which are commonly used for identifying lithospheric structure are concealed by these ice reverberations.
The problematic ice-phase reverberations can, however, be exploited. We describe a practical process, incorporating a simple generalised linear inversion (GLI) stage, which yields an ice-sheet model.
The derived ice model can then be used to design a Wiener filter aimed at attenuating ice phases, and revealing crustal phases in the PRF. Although it is theoretically approximate, the Wiener approach appears robust. Synthetic trialling, using realistic models, is essential for understanding the limitations of the algorithm.
The full process has been applied at ice-covered stations in Antarctica and Greenland. In each case, we have derived robust models for the ice, and have successfully extracted crustal Ps phases from the contaminated receiver functions.
Notes
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References
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