Thanks re the photos. I do take a heavy DSLR camera with a few lenses and a tripod on these kind of walks.
One day I might try just the pocket Pentax Q, but for now I happy to carry the extra 3.5kg.
There are some amazingly steep screes on the face of McKinley.

- Very steep fine screes on a ridge off Mt McKinley
However, we did descend what could be called an active scree coming off McKinley Bluff. There is a photo looking up at its bottom part [Number 23].
It was not really fine material, but in going down this scree you would often place a foot and then surf it down for a metre or 2 until it stabilised again.
I am not sure how you would go about climbing up this one.
This is a shot at a point where it got a bit better - probably because the rocks got a bit bigger and less prone to slipping.

- Coming down the sliding scree from McKinley Bluff