Dune cannibals II

A Piece of Mars: This 0.96×0.54 km (0.60×0.34 mi) scene shows two sets of bedforms (dunes), each aligned in different directions. The more closely-spaced set has sharper crests, and it’s superposed on top of (and it is therefore younger than) the more widely-spaced set. Like a previous post I wrote, the younger set has cannibalized sediment from the older set (although in aeolian geology we say it has “reworked” the sediment). If you click on the image, you might be able to convince yourself that some internal bedding from the older set is being exposed by erosion, but it’s hard to tell for sure at this resolution (maybe we could tell if we had a full resolution HiRISE image to work with here – hmm, maybe I’ll go request one). (HiRISE ESP_045299_1545 NASA/JPL/Univ. of Arizona)