Developing Regionalized Models of Lithospheric Thickness and Velocity Structure Across Eurasia and the Middle East from Jointly Inverting P-Wave and S-Wave Receiver Functions with Rayleigh Wave Group and Phase Velocities
PENN STATE RESEARCH FOUNDATION UNIVERSITY PARK PA
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The main goal of this project is to develop models of lithospheric velocity structure for Eurasia and the Middle East in order to improve capabilities within National Nuclear Security Administration NNSA labs to accurately predict travel times for local and regional phases, as well as travel-times for body waves at upper-mantle triplication distances. Velocity models of the lithosphere are key for accurately modeling not only travel times but also surface-wave dispersion velocities and full waveforms at regional 2 deg - 15 deg and far-regional 15 deg - 25 deg distances. The models are being developed following a two-step approach first, one-dimensional 1D velocity models for select broadband stations are obtained by jointly inverting P- and S-wave receiver functions and fundamental-mode group and phase dispersion velocities second, regionalized velocity models are constructed by combining the 1D joint inversion models within regions used in the UNIFIED model and are validated through regional waveform modeling. We expect the velocity models will also help inform and strengthen ongoing and future efforts within the NNSA labs to develop three-dimensional 3D velocity models for Eurasia and the Middle East, assist in obtaining model-based predictions where no empirical data are available, and improve event locations in regions with sparse network coverage. So far, we have obtained a total of 59 joint inversion models in Eurasia and the Middle East 35 for Europe, 10 for the Middle East, and 14 for Asia. To develop these models, we have considered permanent broadband stations with open access and with waveforms archived at the Data Management Center DMC of the Incorporated Research Institutes for Seismology IRIS. The station distribution is quite uneven among the UNIFIED regions, and the selected stations have been complemented with open stations archived at other data centers when available.
- Geology, Geochemistry and Mineralogy