Hhhhhhrrrrmmm. I see your point. I was assuming that if/when the ice sheet melts, be it climate change or continental drift, eventually bare dirt would show.

Also, I wonder if mining landfills for raw materials, would be profitable. For example, in India trash pickers are able to make a living. Not saying it's wonderful, but on the other hand if all civilization collapses life is going to be pretty shitty for everyone left.