Waveform Modeling of Hydroacoustic Records From Autonomous Mermaid Floats
Description:
We present a computational technique to model hydroacoustic waveforms from teleseismic earthquakes recorded by mid-column MERMAID floats taking into consideration bathymetric effects that modify seismo-acoustic conversions at the ocean bottom and acoustic wave propagation in the ocean layer, including reverberations. Our approach couples spectral-element simulations performed for moment-tensor earthquakes in a one-or three- dimensional solid Earth to a three-dimensional Cartesian fluid-solid coupled spectral-element simulation that captures the conversion from displacement to acoustic pressure at an ocean-bottom interface with accurate bathymetry. We use a wavefield injection methods that couples displacement and traction across the boundary between our modeling domains, which are the entire globe on the one hand, and a smaller portion of the Earth that includes the ocean-bottom interface. One the receiver side the three-dimensional Cartesian fluid-solid coupled spectral-element method honors the three-dimensional bathymetry and captures the conversion of displacement to acoustic pressure. We apply our methodology to over 30,000 seismograms from 3,000 earthquakes recorded by over 60 MERMAID floats over the last 6 years. We compute travel-time residuals by cross-correlating our synthetic seismograms with the observed seismograms to make database suitable for regional seismic tomography with teleseismic earthquakes. We compare our travel-time measurements with measurements made on the same data set by ray-tracing. Our procedure encompasses a complete workflow to close the seismic coverage gap for global tomography by the addition of a fleet of mobile marine sensors, in a manner that can integrate ocean-bottom instrumentation, and traditional land sensors on continents and oceanic islands.
Session: Numerical Modeling in Seismology: Theory, Algorithms and Applications [Poster]
Type: Poster
Date: 4/17/2025
Presentation Time: 08:00 AM (local time)
Presenting Author: Sirawich
Student Presenter: Yes
Invited Presentation:
Poster Number: 126
Authors
Sirawich Pipatprathanporn Presenting Author Corresponding Author sirawich@princeton.edu Princeton University |
Frederik Simons fjsimons@princeton.edu Princeton University |
Nanqiao Du nanqiao.du@mail.utoronto.ca University of Toronto |
Qinya Liu liuqy@physics.utoronto.ca University of Toronto |
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Waveform Modeling of Hydroacoustic Records From Autonomous Mermaid Floats
Session
Numerical Modeling in Seismology: Theory, Algorithms, and Applications