This image shows a large symmetrical alluvial fan at the mouth of a small channel along an unnamed crater. Alluvial fans with a well-defined channel source area are relatively uncommon on Mars.

This fan has a rib-like outer margin and many more terrace-like scarps upslope near the channel mouth. These terraces may indicate the outer margin of sediment deposits during each “pulse” of deposition. Further study of these types of alluvial fans may shed light on past sedimentary environments and conditions on Mars.

Written by: Frank Chuang   (2 March 2008)

This is a stereo pair with PSP_007732_1825 .

More info and image formats at http://hirise.lpl.arizona.edu/PSP_006941_1825

Image: NASA/JPL/University of Arizona