Ancient lake sediments in a crater on Mars

Mars is covered with many bizarre looking formations. For example, the  Univ. of Arizona’s HiRISE camera on the Mars Reconnaissance Orbiter took this picture of what was apparently once the bottom of a lake: HiRISE | Ancient Lake Sediments in a Crater (ESP0371222165)


Zoom in on the crater floor:

From the HiRise page:

This image shows some interesting fractured materials on the floor of an impact crater in Arabia Terra.

There is a channel entering the crater and exiting it (see CTX image). This channel, along with an unusual deposit on the lowest part of the floor, suggests that there was once an ancient lake that deposited sediments here.

Our enhanced-color sample shows layered deposits, some with polygonal patterns, as might be expected from lake sediments. The fracturing of these deposits might have resulted from the sudden breaching of the crater rim, draining the lake.

Written by: Alfred McEwen   (16 July 2014)