Pristine gullies are common on steep slopes in the middle latitudes of Mars, where they are shaped by the action of carbon dioxide frost. There are also pristine gullies in equatorial Valles Marineris where little carbon dioxide frost is deposited.

These equatorial gullies are often associated with recurring slope lineae (RSL); dark thin flows that form at the warmest times on steep slopes. We do not know if the RSL help carve the gullies or if they just follow gullies that formed by some other process.

ID: ESP_080617_1715
date: 7 October 2023
altitude: 263 km

https://uahirise.org/hipod/ESP_080617_1715
NASA/JPL-Caltech/University of Arizona
#Mars #science #NASA