Holden Crater was once filled by at least *two* different lakes. The sediments deposited in those lakes are relatively light-toned where exposed, as we see in this observation.

Each layer represents a different point in time and perhaps a changing environment for Martian life, if it existed. The elongated ridges with sharp crests are sand dunes.

NB: North is to the left in the cutout image.

ID: ESP_011542_1530
date: 11 January 2009
altitude: 259 km

https://uahirise.org/hipod/ESP_011542_1530
NASA/JPL-Caltech/UArizona
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