COLORADO AND THE FOUR GREAT GEOLOGICAL SURVEYS OF 1867-1878

After the Civil War, the United States shifted its attention to the development of the West. The science of geology had also developed through numerous state geological surveys, so that new techniques in mapping and geologic interpretations were available. Four geological surveys were funded by congress in the late 1860’s and 1870’s to describe the geology of the West. They included the Geological and Geographical Survey of the Territories led by Ferdinand Vandeveer Hayden, the Geological Survey of the 40^th Parallel led by Clarence King; the Geological and Geographic Survey of the Rocky Mountain Region led by John Wesley Powell, and the U.S. Survey & Explorations West of the 100^th Meridian led by Lieutenant George M. Wheeler.

Colorado benefited from all of these geological surveys. Colorado was the main focus of the Hayden Survey between 1873 and 1876. The topographic mapping of Colorado by Hayden’s surveyors was so comprehensive that their work was not superseded until after World War II. When the Colorado Atlas was published by the Hayden Survey in 1877, Colorado became the only state that had a detailed geologic map published on a topographic map base. The King and Powell surveys overlapped with the Hayden Survey in northwest Colorado, but the greatest overlap was with the Wheeler Survey that extended into the southwest and south-central part of Colorado. Conflicts arose between the Hayden and Wheeler surveys, both in the field and in Congress.

From the conflicts of the overlapping Surveys in the 1870’s and the great expense of supporting 4 geologic surveys, Congress combined all four surveys into the U.S. Geological Survey in 1879. The first director of the USGS was Clarence King, who served for one year and then was replaced by John Wesley Powell. Hayden was shunted to an administrative role in the early USGS., but his Colorado Atlas became the guide for the USGS maps published after 1879. The USGS set up a Rocky Mountain Division that was based in Denver. This division was headed by Samuel Emmons, who was a member of the King Survey and became one of the founding fathers of American economic geology. Emmons described the geology of the Leadville mining district, and many other mining districts throughout Colorado. He was the first president of the Colorado Scientific Society, founded in 1882.