Once discovered, the impressions may be developed in a similar fashion to friction ridge impressions, with the use of powders or chemicals.
What you look to develop and document is the class and accidental characteristics which may be present in the impression.
A key to the documentation is to photograph from directly above, with light coming from a variety of angles all around the impression. This is a key for both two-dimensional and three-dimensional impressions.
And, for three-dimensional impressions, you may also be able to cast, and create a three-dimensional artifact from the impression.