The way that crater is eroding is very interesting.

What is causing the scalloped erosion? Why is it not eroding uniformly around the rim? I am thinking that perhaps the upper rim bedrock is the same rock layer that contains the blueberries.

We know this rock (evaporate) that contains the blueberries erodes fairly easily in the atmosphere.

On the crater rim, perhaps the bedrock erodes until it is covered by sand. As this happens the “finger’ has erodes into a bay and the former bay starts to become a finger. As this happens , the former bay starts to loose sand until its rock is exposed.

At this point we have had a switch. The former rocky finger has now eroded to a sand covered bay. The former bay has lost its sand and now its rock is exposed as a finger.