Mass wasting triggered by seasonal CO₂ sublimation under Martian atmospheric conditions: Laboratory experiments

Abstract

Abstract Sublimation is a recognized process by which planetary landscapes can be modified. However, interpretation of whether sublimation is involved in downslope movements on Mars and other bodies is restricted by a lack of empirical data to constrain this mechanism of sediment transport and its influence on landform morphology. Here we present the first set of laboratory experiments under Martian atmospheric conditions which demonstrate that the sublimation of CO 2 ice from within the sediment body can trigger failure of unconsolidated, regolith slopes and can measurably alter the landscape. Previous theoretical studies required CO 2 slab ice for movements, but we find that only frost is required. Hence, sediment transport by CO 2 sublimation could be more widely applicable (in space and time) on Mars than previously thought. This supports recent work suggesting CO 2 sublimation could be responsible for recent modification in Martian gullies.