Kyle Doherty sent me the following from Mesa Verde:
"I came across an old decommissioned asphalt road today that appears to be losing ground to some crust. I didn't excavate to see how far it had encroached upon the road, as I didn't want to disturb it. I thought it was pretty cool given the level of development."
It reminds me of an old steel cattle tank I saw near Canyonlands. The rivets had rusted out, and it couldn't hold much water anymore, but had accumulated some soil which grew a nice little crust garden. Even better, Sue Phillips used to have a beer bottle found out in the Mojave desert. Soil had blown in and a biocrust complete with mosses had grown in there as if it were a greenhouse.