The Aeolis region of Mars is full of ancient fluvial (created by flowing water) landforms such as channels and deltas, often with inverted topography: what was down is now up due to differential erosion.

This cutout shows part of the stereo anaglyph. The curving raised feature was a river channel, but coarse sediment or indurated materials made the channel bottom more resistant to erosion so now it is relatively high.

ID: ESP_076507_1735
date: 21 November 2022
altitude: 268 km

https://uahirise.org/hipod/ESP_076507_1735
NASA/JPL-Caltech/University of Arizona
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