Long-runout landslides and the long-lasting effects of early water activity on Mars

Long-runout subaerial landslides (>50 km) are rare on Earth but are common features shaping Mars' Valles Marineris troughs. In this study, we investigated the highly debated emplacement mechanisms of these Martian landslides by combining spectral and satellite-image analyses. Our results suggest that hydrated silicates played a decisive role in facilitating landslide transport by lubricating the basal sliding zone. This new understanding implies that clay minerals, generated as a result of water-rock interactions in the Noachian and Hesperian (4.1-3.3 Ga), exert a long-lasting influence on geomorphic processes that shape the surface of the planet.