Nebraska during the Devonian Period

	400 Ma Lower Devonian Epoch EROSIONAL GAP in the rock record.
	385 Ma Middle Devonian Epoch At this time, a thin sandstone unit is deposited in Nebraska.
	360 Ma Upper Devonian Epoch As the seas rise again, carbonates and shales are deposited across Nebraska.

The images above are Paleozoic paleogeographic maps of the central United States (from Dr. Ron Blakey- http://jan.ucc.nau.edu/~rcb7/ ) that are based on observations in the geologic record. Nebraska is outlined in yellow. Click HERE to visit Dr. Blakey's website to learn more about paleogeography and how the continents have changed position throughout geologic time.

**Image modified after Carlson, M.P., Geology, Geologic Time and Nebraska, Educational Circular No. 10, 1993, University of Nebraska-Conservation and Survey Division, 60p.