Greenhorn Limestone
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The Greenhorn Limestone or Greenhorn Formation is a geologic formation in the Great Plains Region of the United States, dating to the Cenomanian and Turonian ages of the Late Cretaceous period. The fo
The Jetmore Chalk Member of the Greenhorn Formation in Kansas.
The iconic stone posts of Kansas were cut from a layer in the Greenhorn.
Paleoart depicting two large marine predators of the late Cretaceous; Elasmosauridae and Xiphactinus.
Western Interior Seaway
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The Western Interior Seaway was a large inland sea that existed roughly over the present-day Great Plains of North America, splitting the continent into two major landmasses, Laramidia to the west and
A broken concretion with fossils inside; late Cretaceous Pierre Shale near Ekalaka, Montana.
Monument Rocks (Kansas), located 25 miles south of Oakley.
Artist's impression of a Cretoxyrhina and two Squalicorax circling a dead Claosaurus in the Western Interior Seaway
Inoceramus, an ancient bivalve from the Cretaceous of South Dakota.