The Western Interior Seaway formed about 100 million years ago when the mountains that now define western North America lifted up as a result of tectonic forces. Those same forces flexed the land east ...

Trek across this interactive map, ... Explore North America. Publish Date: ... Travel to Monument Rocks to unearth the remains of fish that once lived in a vast inland sea that covered the Midwest.

These Maps Show How North America Was Formed Over 550 Million Years. By Rob Wile. 2012-07-20T16:49:00Z Share. Facebook Email X LinkedIn Copy link. An icon in the shape of ...

Long before the Great Lakes came to define the heart of North America, a much larger lake once ruled the land. Lake Agassiz, a prehistoric inland sea, spread across the continent with a reach that ...

For more than 40 million years, North America's inland sea was filled with giant ammonites like these. But it's one thing to find marine fossils in the flatlands of Kansas.

Situated a whopping 3,700 kilometers (2,342 miles) away from the Atlantic Ocean, it’s the farthest inland port in North America to serve oceangoing ships – and that’s not the only thing that ...

Some people consider the Great Plains of America to be "flyover country." The truth of that pejorative falls outside the realm of science. It is true, however, that 80 million years ago one could not ...