Paleontology and geology
Much of the surface rock exposed in the Panhandle of Oklahoma is Tertiary in age. The Tertiary was a time of broad, gentle uplift in Oklahoma and surrounding areas. Extensive deposits of Tertiary sand and gravel were washed into the state from the west, where the Rocky Mountains were rising. Mammal fossils have been found in some of these deposits. A combination of river, lake, and windblown sand deposits are exposed across the greater part of the High Plains of western Oklahoma. The river sediments contain abundant fossils of mammals, including the remains of horses, camel, mastodons, and rhinoceros. Petrified wood can also be found in these rocks. Lake sediments contain fossil snails, clams, and algae.