Appalachia (Mesozoic)

In the Mesozoic Era (252 to 66 million years ago) Appalachia, named for the Appalachian Mountains, was an island land mass separated from Laramidia to the west by the Western Interior Seaway. The seaway eventually shrank, divided across the Dakotas, and retreated towards the Gulf of Mexico and the Hudson Bay. This left the island masses joined in the continent of North America as the Rocky Mountains rose.

From the Turonian to the end of the Campanian ages of the Late Cretaceous, Appalachia was separated from the rest of North America. As the Western Interior Seaway retreated in the Maastrichtian, Laramidia and Appalachia eventually connected. Because of this, its fauna was isolated, and developed very differently from the tyrannosaur, ceratopsian, pachycephalosaur and ankylosaur dominated fauna of the western part of North America, the geologist's "Laramidia". Due to numerous undiscovered fossiliferous deposits and due the fact that half of Appalachia's fossil formations being destroyed by the , little is known about Appalachia, with exception of plant life and the insects trapped in amber from New Jersey. Many of the various fossil formations not destroyed by the Pleistocene ice age still remain elusive to the field of paleontological study. In addition, due to a lack of interest in Appalachia, many fossils that have been found in Appalachia lie unstudied and remain in the inaccurate genera to which they were assigned in the days of E.D. Cope and O.C. Marsh. However, the area has seen a bit of a resurgence of interest due to several discoveries made in the past few years. As mentioned earlier, not much is known about Appalachia, but some fossil sites, such as the Navesink Formation,Ellisdale Fossil Site,Mooreville Chalk Formation, Demopolis Chalk Formation, Black Creek Group and the Niobrara Formation have given us a glimpse into this forgotten world of paleontology.

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