Analysis of Orbital Sounding in Context With In‐Situ Ground Penetrating Radar at Jezero Crater, Mars

Abstract

The RIMFAX ground‐penetrating radar (GPR) on Mars2020 Perseverance Rover is the first GPR operated on the Martian surface since February 2021, searching for stratigraphy beneath the Jezero crater. During its operations, GPR detected several strong reflectors extending from the exposed section of the Séitah formation down to depths of 15 m, with derived relative permittivity of ∼9.0 consistent with low‐porosity mafic rocks. We reprocessed all the SHAllow RADar (SHARAD) observations at a higher resolution and combined repeat‐passes coherently and/or incoherently for clutter mitigation. We then examined the bright returns searching for subsurface structures. The reprocessed data did not show any shallow reflectors like those detected by RIMFAX. We investigated possible factors influencing the lack of shallow reflectors in SHARAD radargrams, including the properties of the older volcanic lithologies and the significant variability of subsurface reflectors within the SHARAD km‐wide spatial footprint, which prevents the formation of coherent reflections.