Evidence for a Diagenetic Origin of Vera Rubin Ridge, Gale Crater, Mars: Summary and Synthesis of Curiosity’s Exploration Campaign

This paper provides an overview of the Curiosity rover’s exploration at Vera Rubin ridge and summarizes the science results. Vera Rubin ridge (VRR) is a distinct geomorphic feature on lower Aeolis Mons (informally known as Mt. Sharp) that was identified in orbital data based on its distinct texture, topographic expression, and association with a hematite spectral signature. Curiosity conducted extensive remote sensing observations, acquired data on dozens of contact science targets, and drilled three rock samples from the ridge, as well as one rock sample immediately below the ridge. Strata comprising VRR were deposited in a predominantly lacustrine setting and are part of the Murray formation. The rocks within the ridge are chemically in family with underlying Murray formation strata. Red hematite is dispersed throughout much of the VRR bedrock, and this is the source of the CRISM orbital detection. Gray hematite is also present in isolated, gray-colored patches concentrated towards the upper elevations of VRR, and the gray patches contain small, dark Fe-rich nodules. We that propose VRR formed when diagenetic event(s) preferentially hardened rocks, which were subsequently eroded into a ridge by wind-erosion. This process also led to enhanced crystallization and/or cementation that deepened the ferric-related spectral absorptions on the ridge that are readily distinguishable from orbit. Results add to existing evidence of protracted aqueous environments at Gale crater and give new insight into how diagenesis shaped Mars’ rock record.