Seismo Lab Brown Bag Seminar

Wind turbulence-induced ground motion (WTGM) on Mars has significantly impeded our interpretation of seismic data retrieved from the InSight mission. However, most features of WTGM remain elusive due to the single-seismometer constraint, WTGM's distinct stochastic properties and the limited understanding of wind turbulence-ground interaction. In this study, we aim to develop a deeper understanding of WTGM by considering its underlying physics. We first derive the theory for wind turbulence-ground interaction and apply the Kolmogorov slope, a measure of power spectral density (PSD), to WTGM as a temporally robust physical variable. We show that the Kolmogorov slope from InSight seismic data is consistent with the theory and demonstrates its potential for identifying previously undetected wind-masked marsquakes. Second, we explain spectra frequency drift, one of WTGM's dominant features, by using Soil-Structure Interaction (SSI) theory. SSI further enables the inversion of the diurnal variation in the elastic stiffness of the regolith beneath the InSight lander. Lastly, we reexamine established studies of WTGM on Earth and demonstrate that our theory can permit more quantitative analyses and a better understanding of atmospheric conditions.