My guess: crater rim
Scanning left from the dark "anthill" mound, there are three more hummocks of about the same height above the local surface. Two are just below a dark spot that seems to be on the hillside; of those, the left-hand one looks to be superimposed on (i.e., nearer than) the right-hand one. The fourth hummock is about the same distance farther to the left of the central two.