Does this observation show a possible proto-pedestal crater?

This crater has a ring trough, but the inner circle around the crater does not appear significantly elevated. Why did the ring around the crater collapse before anything else? Could it be an example of ice sublimating from below the surface?

A high resolution image shows us better details, as we can see in this close-up .

Written by: HiRISE Science Team (audio by Tre Gibbs)   (13 November 2013)

More info and image formats at http://hirise.lpl.arizona.edu/ESP_033242_2315

Image: NASA/JPL/University of Arizona