Samuel Epstein (geochemist)

Samuel Epstein (December 9, 1919 – September 17, 2001) was a Canadian-American geochemist who developed methods for reconstructing geologic temperature records using stable isotope geochemistry. He was elected to the United States National Academy of Sciences in 1977, and a fellow of the Royal Society of Canada in 1997.

Samuel Epstein
Born(1919-12-09)December 9, 1919
DiedSeptember 17, 2001(2001-09-17) (aged 81)
Alma materMcGill University,
University of Manitoba
Known forHelped establish the fields of stable isotope geochemistry,
carbonate paleothermometry
AwardsWollaston Medal (1993)
V. M. Goldschmidt Award (1977)
Urey Medal (European Association of Geochemistry) (1995)
Scientific career
FieldsGeochemistry, Chemistry
InstitutionsCalifornia Institute of Technology,
University of Chicago,
Canadian Atomic Energy Project
Doctoral advisorCarl A. Winkler
Doctoral studentsRobert N. Clayton
Hugh P. Taylor Jr.

Early years

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Sam Epstein was born in Kobryn, Belarus, then part of Poland, and as a child his family emigrated to Winnipeg, Manitoba. After receiving a B.Sc. in Geology and Chemistry (1941) and a M.Sc. in Chemistry (1942) from the University of Manitoba, Epstein completed his Ph.D. at McGill University under the supervision of Carl A. Winkler in 1944. His thesis focused on the synthesis and reaction kinetics of high explosives, including RDX and HMX. Epstein subsequently worked for the Canadian Atomic Energy Project for several years.

Career

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In 1947, Epstein moved to the United States to begin a research fellowship with Harold Urey's group at the University of Chicago. While at Chicago, Epstein, along with Ralph Buchsbaum, Heinz A. Lowenstam, C. R. McKinney and others developed the carbonate-water isotopic temperature scale, allowing ancient ocean temperatures to be determined from precise measurements of 18O/16O in geological samples of calcium carbonate.[1] This method is still the most widely used geochemical climate proxy for locations and times not sampled in ice core records.

Epstein joined the faculty of the California Institute of Technology in 1952, and continued to explore the new field of stable isotope geochemistry. He and his students used mass spectrometry to study natural variations in the isotopic abundances of hydrogen, carbon, oxygen and silicon, with applications to archeology, biochemistry, climatology, and geology. He was awarded the Wollaston Medal of the Geological Society of London in 1993.[2]

Epstein remained at Caltech as a Professor and Professor Emeritus until shortly before his death on September 17, 2001.

The European Association of Geochemistry awards a Science Innovation Award medal every five years named in his honour for work in isotope geochemistry.

References

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  1. ^ S. Epstein; R. Buchsbaum; H. A. Lowenstam & H. C. Urey (1951). "Carbonate-water isotopic temperature scale". Geological Society of America Bulletin. 62 (4): 417–426. doi:10.1130/0016-7606(1951)62[417:CITS]2.0.CO;2.H. C. Urey; H. A. Lowenstam; S. Epstein; C. R. McKinney (1951). "Measurement of paleotemperatures and temperatures of the Upper Cretaceous of England, Denmark and the Southeastern United States". Geological Society of America Bulletin. 62 (4): 399–416. doi:10.1130/0016-7606(1951)62[399:MOPATO]2.0.CO;2.
  2. ^ "Wollaston Medal". Award Winners since 1831. Geological Society of London. Archived from the original on 2010-08-19. Retrieved 2009-02-25.
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