Geoworld -- "Prehistoric Wyoming"

A sea floor from the Ordovician Era. (click for source)"

Wyoming is one of the most geologically rich areas of the United States. Paleontologists have found numerous prehistoric fossils there while mining, oil, and gas drilling are key industries of the state in modern times.

Geoworld provides an overview of Wyoming's geological history, divided into the different geological eras. The oldest fossils found are stromatolites (algae/microbial remnants) dated at 1.7 billion years old. They are located, curiously enough, very near to the peaks of Wyoming's Rocky Mountains, which have only been formed in the "recent" Laramide orogency -- starting 80 million years ago.

A large potion of Wyoming's famous dinosaur fossils date to the Jurassic period -- starting 199 million years ago. Long before that time, Wyoming was covered by an ocean. Numerous aquatic fossils from the Ordovician Period (starting 488 million years ago) are also buried beneath the state's landscape.

Wyoming is currently the most sparsely populated state in America. Its key economic industries are coal mining and oil/natural gas drilling -- a legacy of its geological past.