Clarence Samuel Ross (20 September 1880, Eldora, Iowa – 19 April 1975, Rockville, Maryland) was an American mineralogist, petrologist, and economic geologist.[1][2] His 1961 paper on ash-flow tuffs, coauthored with Robert Leland Smith (1920–2016),[3] has at least 600 citations.
Biography
Ross received from the University of Illinois his A.B in 1913, A.M. in 1915, and Ph.D. in 1920. He joined the U.S. Geological Survey in 1917. The survey first assigned him the task of mapping oil lands in Osage County, Oklahoma, where he studied bentonitickeyhorizons. In the summer of 1917 he was sent to the southern Appalachian region to study copper deposits
of the Ducktown type. In 1919, with Esper S. Larsen, Jr., he made geologic maps of the southern end of the San Luis Valley in New Mexico.[2] In the early 1920s he published several reports with Hugh D. Miser.
His early studies with Hugh D. Miser were made on the diamond-bearing peridotite in Pike County, Arkansas, and are models of description and interpretation. Subsequently, he published papers on rhyolite and lamprophyricdike rocks. His interest in volcanic pyroclastic rocks began at least as early as 1925, when he published with Earl V. Shannon of the U. S. National Museum a series of papers on bentonite, and culminated in his paper with Robert L. Smith on ash-flow tuffs.[1]
Ross's versatility and broad range of interests are shown by the major topics listed in his bibliography of 121 titles: they covered mineralogy and occurrence of clay minerals, geology of copper deposits of the Southern Appalachians, petrology of rhyolitic welded tuffs, mineralogy and petrology of titanium deposits in Virginia, and comparison of peridotite and pyroxenite with ultramafic nodules in basalts. Ross's contributions to clay mineralogy during more than twenty years in collaboration with P. F. Kerr, S. B. Hendricks, and E. V. Shannon have been fundamental to study of wall-rock alteration related to ore deposits and to understanding of weathering deposits.[2]
On 2 November 1918, Ross married Helen Hall Frederick,[8] who died in 1968. Their children were Betsy Ross Jones and Malcolm Ross, who became a geochemist with the U.S. Geological Survey.[1]