The geological perspective of Terra is bizarrely reassuring. Humans will presumably be gone within a few million years, perhaps sooner. If the past that Novacek describes is a guide to the future, global ecosystem processes will be restored some tens of thousands of years to a million years after our demise, and new forms of life over the ensuing millions of years will exploit the denuded planet we leave behind. Thirty million years on, things will be back to normal, albeit a very different 'normal' from before. It is good the be optimistic. The problem is living here in the meantime.
I think it's safe to say the tree-huggers have gone off the deep end when their view of eutopia is a world without us.