Samuel Franklin Emmons (March 29, 1841 – March 28, 1911) was an American geologist. He was born in Boston, Massachusetts. He graduated from Harvard University in 1861 and studied at the Ecole des Mines in Paris, France, from 1862 to 1864 and at the Freiberg (Saxony) mining school in 1865. In May 1867, he was appointed assistant geologist under Clarence King on the American geological exploration of the fortieth parallel, and in July 1879 became geologist in charge of the Colorado division of the United States Geological Survey. He traveled extensively throughout the United States in connection with his work, and in 1870 made a survey, along with A. D. Wilson, of Mount Rainier, the highest and most inaccessible peak in the Cascade Range. The largest glacier in the contiguous United States,