"Map of the United States Exhibiting the Present Status of Knowledge Relating to the Areal Distribution of Geologic Groups", U.S. Geological Survey (USGS)

This is the first published geological map of the United States by the nascent USGS. Legend names and color codes twelve different geological formations. There is also very fine detail of hydrology. Vast areas of the western US remain blank reflecting the infancy and inadequacy of western geological explorations at the time, and coincidentally emphasizing the need for more congressional funding. The mapping of the King, Hayden, Powell and Wheeler surveys are evident in the west, but little else. This was Plate II in the annual report.

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Condition: A

Folding as issued. One fold with a little toning, otherwise fine with bright coloring and full margins.