Light-Toned Layered Deposits on Southern Mid-Latitude Crater Floor

This image features the floor of a crater in the Southern highlands of Mars.

The light-toned layered deposits (LTLD) are located in the center of the image; they are exposed along the edges of the high-standing mesa. LTLD are found in many places on Mars, including impact craters and canyons near the equator. They may have been deposited by sedimentary processes involving wind and/or water.

Dunes or ripples surround the mesa. The orientation of the dunes indicates that the direction of the dominant wind at the time of the dune/ripple formation was along the troughs that surround the mesa.

The terrain near the bottom of the image has a texture that geologists call “etched.” The etched texture is a result of differential erosion as some materials being eroded more easily than others. One possible scenario is that the region was buried by a soft sedimentary deposit that is now being removed by wind erosion.

Written by: Kelly Kolb   (15 April 2009)

This is a stereo pair with ESP_011811_1395 .

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Image: NASA/JPL/University of Arizona