Look around, do you see layers of sediments in your area, are there fossils in your area?
we have some wonderful deposits of tertiary fossils in my area. i have had the benefits of seeing mostly complete early whale skeletons laid out on the floor of the "temporary" buildings at the local university, as a child. (i actually own a vertebrae and rib of one such whale)
we also have some great examples of saber-toothed cats and giant sloths in some nearby areas.