Evaluation of S1222a Source Parameters Based on Site Effect Simulation and Implication for the Event Origin

Abstract

Studying the source characteristics of marsquakes can not only help to reveal the current geological features and thermal state (temperature and pressure) of the marsquake source regions, but also provide information on the evolution history of the corresponding regions. NASA's InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission (Banerdt et al., 2020;Banfield et al., 2020;Lognonné et al., 2020) has revealed that Mars is seismically active today, with many of the marsquakes located in Cerberus Fossae (Giardini et al., 2020;Stähler et al., 2022). Centroid moment tensor inversion was applied to some of these marsquakes (Brinkman et al., 2021;Jacob et al., 2022; Sita & van der Lee, 2022). However, the tectonic setting, such as fault movement, magmatic activity, or mass wasting, in most regions of Mars remains to be discovered, which relies on the analyses of marsquakes in the regions of interest.The source characteristics of a marsquake are described by its source spectrum, such as the classical ω 2 model in terrestrial seismology (Aki & Richards, 2002), in which the seismic spectra decay with frequency by the power of 2. Spectral analysis is a classical technique to constrain the source spectrum of a quake, and to estimate the seismic spectra as a key parameter. Corner frequency estimation is commonly applied to investigate the source features of a quake (e.g., Boatwright, 1984;Brune, 1970;Madariaga, 1976). On Earth, corner frequency estimation has been conducted for different regions to estimate the stress drops at source regions (e.g., Allmann &