Pristine Noachian crust and key geologic transitions in the lower walls of Valles Marineris: Insights into early igneous processes on Mars

► A complete morphologic and mineralogic survey of the entire walls. ► No sedimentary layers were observed within the walls thus far. ► Preserved pre-Noachian pristine crustal material is exposed in the walls. ► This pristine material has characteristics in agreement with martian meteorites. ► Western and eastern Valles Marineris seem emplaced into different materials.