Sol 4415-16, June 25-26, 2016. This little flat-topped feature, a mini-mesa sitting on the floor of Marathon Valley with the profile of a tree-stump, is probably an erosional remnant. The Navcam composite view was taken on Sol 4415 and looks northward toward Hinners Point.
Below is a Pancam view taken on Sol 4416 (false color by Holger Isenberg) of the mini-mesa remnant. The reddish tints in the false-color view suggest the mesa rock and its nearby surroundings may contain clay minerals. Both images enlarge when clicked.