WHITMAN CROSS AND RICHARD ALEXANDER FULLERTON PENROSE, JR.: THE FIRST SCIENTISTS TO INVESTIGATE THE GEOLOGY OF CRIPPLE CREEK, COLORADO

The Cripple Creek Mining District, located on the western slope of Pikes Peak, Colorado, was established in 1891 when underground mining sought high-grade gold telluride veins. In 1894, the U.S. Geological Survey (USGS) sent two geologists to conduct fieldwork and prepare a report on the geology and mines of the Cripple Creek goldfields. The geologists were Whitman Cross, one of the founders of the Colorado Scientific Society (CSS), and Richard A.F. Penrose Jr., the Geological Society of America's (GSA) most noted benefactor.

Whitman Cross (1854-1949) was a prominent field geologist for the USGS. He did most of his work in the Colorado Rockies, mapping large areas of southwestern and central Colorado. Much of his mapping was in rugged country, requiring travel by foot, horseback, and pack train. His major field areas were related to new mining districts and included Crested Butte, Telluride, Rico, and the San Juan Mountains. His field camps were recognized as excellent training opportunities for young geologists.

Richard A. F. Penrose, Jr. (1863-1931) was a mining geologist and investor who eventually accumulated great wealth through mining investments. Penrose received his Ph.D. at the age of 23. He worked on mapping assignments in Arkansas, Texas, Arizona, and Colorado for the USGS and was also employed as a private mining consultant. Penrose was editor of the Journal of Geology and on the University of Chicago faculty under T.C. Chamberlain.

The Cross and Penrose report on Cripple Creek was published in 1895, and included a geologic map based on a representative rock collection they made. The rock collection, now on display in the Cripple Creek District Museum, formed the foundation of the report. The report was the first scientific publication on the district and was used by mine owners to raise capital for the expansion of their mining operations.

The CSS and GSA have benefited from the membership of Whitman Cross and Richard A. F. Penrose, Jr.