It's easy to underestimate the size of Victoria by looking at the images taken by Opportunity so far. It's much bigger than it seems, but not much deeper. Look at the photographs from space - there are wide ledges along the rim. They look very steep in the MER images.
I believe the diameter to depth ratio for rocky meteorites is 10:1. If Victoria is 800m wide, its initial depth must have been 80m, and now it's 40 or so. That's a lot of stuff! The bigger the crater, the more is the ratio of the volume displaced by the impact to the volume displaced by erosion in the given time.

>explain its morphology

It's a crater.

--Bill

Ah, right. Now where's that smarta$$ smiley when you need it?

Bill, thanks for posting the Meteor crater formation. That looks like a good starting point for Victoria.

I know we don't have a realistic estimate for Victoria's age yet (other than "old"), but I want to keep in mind that Mars' atmosphere might well have been more substantial, enough to have more effect on wind-driven erosion of the cliff walls. Do we have any useful estimates of Martian atmospheric density over the life of the planet?

Boundary between original surface and ejacta blanket? I see some blocks that appear to have layering at an angle though it is difficult to tell with the jpeg artifacts. Material below line reminds me of top, evaporite, layer in Endurance

Alan, I've not got this one figured out either. The lower, arcuate part looks like a failure surface along impact-induced fractures. Above that it looks jumbled like ejecta. Then above that is a well-defined horizontal layer, with sand above that. Very complex.

--Bill

I agree; this is some complex stratigraphy. Alan has picked the lower boundary of what might be called a 'megabreccia'. And certainly there is a fine-grained lighter colored layer at the very top. It looks as if there is another layer of jumbled rocks between these two. In a couple of places the layer appears to have draped over the boulders of the 'megabreccia'.
The layer immediatly below alan's yellow line is also highly fractured. But the fragments here are more similar in size than the jumble of boulders and debris in the 'megabreccia' above the yellow line.
I'd be very reluctant to try to make any correlations with Endurance at this point.
That's my take anyway.
This is going to take some time and more images to figure out.

Perhaps the layer just below the fine surface coating is lava flows that 'draped' over the Megabreccia, then got soaked in water. The thin top layer is probably what has been quietly accumulating since things quieted down on the planet.