rocks, and in field studies of rhyolitic extrusive rocks. His field work took him to New England, and to all of the western states. In 1954, he began a long and productive period of work in Elko County, Nevada, where he studied rhyolites, stratigraphy and structure, and mapped the geology of the Jarbidge, Owyhee, Mountain City and Tuscarora 15’ quadrangles. He relocated to Menlo Park, California in 1956, but spent most summers with his family in a field camp in Nevada. Many of his 70 publications were based on his work in this period, which culminated in his 1987 synthesis report on the Geology of Elko County, a complex area the size of Connecticut and Massachusetts together. The 1:250,000 scale map for the report has a total of 109 mapping units, with areas mapped as small as 10 ha. Although most of his professional career was spent outside of academia, Coats enjoyed mentoring and teaching one-on-one. Many of his former field assistants and protégés have gone on to illustrious careers in universities and government service. Coats was married for 58 years to Elizabeth Robinson Coats. He died peacefully at his home in Aptos, California, on January 12, 1995. He was survived by two sons (David of Minneapolis and Robert of Berkeley) and a daughter (Katherine Mrache, of Aptos), and seven grandchildren. Selected publications References 1910 births 1995 deaths 20th-century American geologists Canadian emigrants to the United States University of Washington alumni University of California, Berkeley alumni University of Alaska Fairbanks faculty People from Marshalltown, Iowa United States Geological Survey personnel Scientists from Toronto People from Aptos, California Tectonicists