¹M. C. Deahn et al. (>10)
Journal of Geophysical Research: Planets, 131, e2025JE009471
Open Access Link to Article [DOI: 10.1029/2025JE009471]
¹Purdue University, West Lafayette, IN, USA

Published by arrangement with John Wiley & Sons

The Mars 2020 rover is currently traversing the western rim of Jezero, a Middle to Late Noachian‐aged crater formed by an impactor that struck the northwest edge of Isidis Planitia (hereafter referred to as theIsidis basin) on Mars. Previous studies suggest that pre‐Isidis basin and Noachian outcrops are preservedthroughout this region; however, the nature of these exposures in the Jezero crater rim is unclear. It has beenhypothesized that crater‐forming processes should expose these ancient crustal rocks in the Jezero craterrim—presenting a unique opportunity to explore ancient Mars outcrops that are otherwise typically buried byyounger units. Jezero’s rim has undergone extensive erosion and modification since its formation ∼3.9 billionyears ago. To investigate these ancient lithologies, the Mars 2020 Science Team produced a 1:2500 scalegeologic map and interpreted a bedrock map of the ∼14.5 × 3.5 km area around the western Jezero crater rim.We identified, mapped, and defined nine bedrock units on Jezero crater’s rim to make connections to regionalgeologic units and identify deposits or features unique to Jezero crater. We found that the rim likely preserves arecord of pre‐Isidis bedrock, the Isidis and Jezero impacts, and post‐impact geologic processes. We alsoobserved candidate megabreccia, hydrothermal ridges, and regional volcanics that may be targets for futurerover‐based investigations. Our results show that in situ investigation of pre‐Isidis and Noachian‐agedlithologies preserved on the rim will provide insight into the nature of Mars’ early crustal formation andcratering processes.