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
Karoo Ice Age Karoo Ice Age The Karoo Ice Age, more commonly referred to as the Late Paleozoic Ice Age, from 360–260 million years ago (Mya) was the second major ice age of the Phanerozoic Eon. It is named after the tillite (Dwyka Group) found in the Karoo Basin of South Africa, where evidence for this ice age was first clearly identified in the 19th century. The tectonic assembly of the continents of Euramerica (later with the Uralian orogeny, into Laurasia) and Gondwana into Pangaea, in the Hercynian-Alleghany Orogeny, made a major continental land mass within the Antarctic region, and the closure of