Tyler B. Coplen, Ph.D.
Dr. Tyler Coplen is the Director of the Reston Stable Isotope Laboratory of the USGS Water Resources Mission Area.
Tyler B. Coplen is an ST scientist in geochemistry. His research focuses on isotope hydrology, development of innovative analytical techniques for isotopic analysis of light elements, provides forensic-quality analytical services to USGS programs, and creates isotopic reference materials for calibration of mass spectrometers and laser absorption spectrometers in isotope laboratories worldwide. In 1974, he joined the U.S. Geological Survey, and in 1978, he set up the Reston Stable Isotope Laboratory, please visit the Reston Stable Isotope Laboratory website. He set up and led the Subcommittee on Natural Isotopic Fractionation (1985–2002) of the International Union of Pure and Applied Chemistry (IUPAC) that resulted in a dozen elements being assigned standard atomic-weight values that are intervals, instead of single values, to indicate that atomic-weight values of many elements are not constants of nature.
Professional Experience
Assistant Research Geochemist, University of California, Riverside 1970–1974
Education and Certifications
Ph.D. 1970, University of Chicago, Department of Geophysical Sciences, Advisor: Prof. Robert N. Clayton
M.S. 1968, University of Chicago, Department of Geophysical Sciences
B.S. 1966, Pacific Lutheran University, Major: Physics
Affiliations and Memberships*
Honorary Member, Commission on Isotopic Abundances and Atomic Weights of the International Union of Pure and Applied Chemistry
Science and Products
Standard and conventional atomic weights 2016 abridged to four significant digits
Four-place table of standard atomic weight values of hydrogen through uranium compared since 1961
Most Earth-surface calcites precipitate out of isotopic equilibrium
Erratum to: Isotope-abundance variations and atomic weights of selected elements: 2016 (IUPAC Technical Report)
Isotopes matter
IUPAC Periodic Table of the Elements and Isotopes (IPTEI) for the education community (IUPAC Technical Report)
Seeking excellence: An evaluation of 235 international laboratories conducting water isotope analyses by isotope-ratio and laser-absorption spectrometry
Clarification of the term “normal material” used for standard atomic weights (IUPAC Technical Report)
Preliminary assessment of stable nitrogen and oxygen isotopic composition of USGS51 and USGS52 nitrous oxide reference gases and perspectives on calibration needs
New biotite and muscovite isotopic reference materials, USGS57 and USGS58, for δ2H measurements–A replacement for NBS 30
Clarifying atomic weights: A 2016 four-figure table of standard and conventional atomic weights
Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer–chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS)
Antarctic ice-core water (USGS49) – A new isotopic reference material for δ2H and δ18O measurements of water
New organic reference materials for hydrogen, carbon, and nitrogen stable isotope-ratio measurements: caffeines, n-alkanes, fatty acid methyl esters, glycines, L-valines, polyethylenes, and oils
Science and Products
Standard and conventional atomic weights 2016 abridged to four significant digits
Four-place table of standard atomic weight values of hydrogen through uranium compared since 1961
Most Earth-surface calcites precipitate out of isotopic equilibrium
Erratum to: Isotope-abundance variations and atomic weights of selected elements: 2016 (IUPAC Technical Report)
Isotopes matter
IUPAC Periodic Table of the Elements and Isotopes (IPTEI) for the education community (IUPAC Technical Report)
Seeking excellence: An evaluation of 235 international laboratories conducting water isotope analyses by isotope-ratio and laser-absorption spectrometry
Clarification of the term “normal material” used for standard atomic weights (IUPAC Technical Report)
Preliminary assessment of stable nitrogen and oxygen isotopic composition of USGS51 and USGS52 nitrous oxide reference gases and perspectives on calibration needs
New biotite and muscovite isotopic reference materials, USGS57 and USGS58, for δ2H measurements–A replacement for NBS 30
Clarifying atomic weights: A 2016 four-figure table of standard and conventional atomic weights
Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer–chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS)
Antarctic ice-core water (USGS49) – A new isotopic reference material for δ2H and δ18O measurements of water
New organic reference materials for hydrogen, carbon, and nitrogen stable isotope-ratio measurements: caffeines, n-alkanes, fatty acid methyl esters, glycines, L-valines, polyethylenes, and oils
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government