One of the AAPG projects is the preparation of a new Geological Map of the United States with a superimposed highway network. The map, on a scale of 1:1,875,000, will include the 48 conterminous states. It is being published in 11 parts, each covering a region of approximately 270,000 sq mi, printed on a 28 × 36-in. sheet.

Six regional maps have been published and the remaining 5 are 25-75% complete. A new base map has been prepared from information furnished by the USGS. Information from the USGS, the various state geological surveys, and other sources is synthesized to produce the various elements on the map.

Approximately 50 overlays are prepared for the front side of each regional map. Good registry is achieved by use of a pin registry system. About 50 colors are used on each regional map; over 100 colors will be used in the series. The maps are printed on a 4-color press.

Upon completion of the series AAPG will have (1) a geologic map of the United States; (2) about 50 related columnar sections; (3) a geologic cross section network of about 19,000 mi in length; (4) a set of paleogeographic maps of the United States by epochs showing deposition, uplift, and igneous activity; and (5) a subjective tectonic map of the United States.

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