Samuel Emmons devoted 30 years of active, loyal service to the United States Geological Survey, leaving behind a legacy of incomparable contributions to geological science in the form of field work and documents covering a wide range of geological subjects. The majority of these writings are of extreme value and demonstrate his talent of presenting geological details clearly, honestly and with penetrating vision.
In 1866, Emmons began his brilliant career as assistant to Clarence King on the famous geological exploration of the 40th Parallel. The group was required to survey an area 100 miles wide that stretched from the Great Plains of Wyoming and Colorado westward to California’s eastern border. Always included in their survey was the proposed route of the first Transcontinental Railroad. The fieldwork was finally completed in 1872. Emmons’ great contribution to this exploration will be found in his report on the Descriptive Geology.
In 1879, when Clarence King organized the Bureau of Geological Survey, he appointed Emmons Geologist in Charge of the Rocky Mountain Division. He immediately began preparing an in-depth monograph on the Leadville, Colorado mining district. He conquered the details of the complex ore bodies and the monograph and atlas—Geology and Mining Industry of Leadville—appeared in 1886. This great scientific work attracted immediate attention, not only by geologists and miners, but all classes of scientific men. It won for its author an international reputation. No single publication of the Geological Survey has since exerted a more beneficial influence and stimulated more discussion. The volume became a model for all geologists, both young and old.
Emmons also published the now-famous paper, “The Secondary Enrichment of Ore Deposits,” and authored papers on the mining areas of Colorado, Montana, Utah, the Cananea Mining District of Mexico and the Cobalt Mining District of Ontario.
Samuel Emmons was highly respected and well loved by those in his profession and, when he died, he left behind a noble record of a life of service well performed.
