Geology of Ohio terrestrial environment since the Permian. For instance, the main subdivisions of the Pennsylvanian: the Pottsville Group, Alleghany Group, Conemaugh Group and Monongahela Group, along with the Early Permian Dunkard Group, are each more terrestrial than the last. The region was situated inland, experiencing terrestrial erosion as the Proto-North American continent of Laurasia collided with Gondwana to form the supercontinent Pangaea. Rocks from the end of Paleozoic are best exposed in road cuts along I-77, between Canton and Marietta, I-77 from Cambridge to Bridgeport and cliffs on the Ohio River north of Marietta to East Liverpool. For 245 million years, spanning
Mandla Plant Fossils National Park some work on the plant fossils of Mandla, though the study is yet in a preliminary stage. In Ghuguwa and Umaria the standing, petrified trunks of trees have been identified as Gymnosperms and Angiosperms- Monocotyledons and palms. There are certain Bryophytes also. There is some question about whether the fossils are from the late Jurassic or the early and mid Cretaceous age. This is because when the breakup of the single land mass, Pangaea occurred, it was split by the continental drift into Laurasia and Gondwana somewhere between the Jurassic and Cretaceous ages. India formed a part of Gondwana. Depending