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
Filter Total Items: 18
No Result Found
Filter Total Items: 153
Continuous 500,000-year climate record from vein calcite in Devils Hole, Nevada Continuous 500,000-year climate record from vein calcite in Devils Hole, Nevada
Oxygen-18 (δ18O) variations in a 36-centimeter-long core (DH-11) of vein calcite from Devils Hole, Nevada, yield an uninterrupted 500,000-year paleotemperature record that closely mimics all major features in the Vostok (Antarctica) paleotemperature and marine δ18O ice-volume records. The chronology for this continental record is based on 21 replicated mass-spectrometric uranium-series...
Authors
I.J. Winograd, T.B. Coplen, J.M. Landwehr, A.C. Riggs, Kenneth R. Ludwig, Barney J. Szabo, Peter T. Kolesar, K.M. Revesz
Reporting of nitrogen-isotope abundances (Technical Report) Reporting of nitrogen-isotope abundances (Technical Report)
To eliminate possible confusion in the reporting of nitrogen-isotope analyses, the Commission on Atomic Weights and Isotopic Abundances recommends that the value 272 be employed for the 14N/15N value of N2 in air for calculating atom percent 15N from measured δ15N values.
Authors
Tyler B. Coplen, H.R. Krouse, J.K. Bohlke
Improvements in the gaseous hydrogen-water equilibration technique for hydrogen isotope ratio analysis Improvements in the gaseous hydrogen-water equilibration technique for hydrogen isotope ratio analysis
Improved precision in the H2-H2O equilibration method for δD analysis has been achieved in an automated system. Reduction in 1-σ standard deviation of a single mass-spectrometer analysis to 1.3‰ is achieved by (1) bonding catalyst to glass rods and assigning use to specific equilibration chambers to monitor performance of catalyst, (2) improving the apparatus design, and (3) reducing the...
Authors
T.B. Coplen, J. D. Wildman, J. Chen
Caution on the use of Viton® or FETFE® O-rings in carbon dioxide sample containers for δ180 analysis Caution on the use of Viton® or FETFE® O-rings in carbon dioxide sample containers for δ180 analysis
After 10 days, 3-μmol CO2 samples in containers having glass stopcocks with Viton® or FETFE O-rings were enriched in 18O by 1.5% as a result of absorption by the elastomer; this amount of enrichment is ∼20 times greater than the precision of δ18O measurements of most laboratories. No change in 13C content was observed. Increasing the sample size to 100 μmol resulted in an 18O enrichment...
Authors
Kinga M. Revesz, Tyler B. Coplen
Gas chromatographic separation of carbon dioxide and nitrous oxide for stable isotopic analysis of carbon dioxide Gas chromatographic separation of carbon dioxide and nitrous oxide for stable isotopic analysis of carbon dioxide
No abstract available.
Authors
Kinga Revesz, Tyler B. Coplen
A 250,000-year climatic record from Great Basin vein calcite: Implications for Milankovitch theory A 250,000-year climatic record from Great Basin vein calcite: Implications for Milankovitch theory
A continuous record of oxygen-18 (δ18O) variations in the continental hydrosphere during the middle-to-late Pleistocene has been obtained from a uranium-series dated calcitic vein in the southern Great Basin. The vein was deposited from ground water that moved through Devils Hole—an open fault zone at Ash Meadows, Nevada—between 50 and 310 ka (thousand years ago). The configuration of...
Authors
Isaac J. Winograd, Tyler B. Coplen, Barney J. Szabo, Alan C. Riggs
Normalization of oxygen and hydrogen isotope data Normalization of oxygen and hydrogen isotope data
To resolve confusion due to expression of isotopic data from different laboratories on non-corresponding scales, oxygen isotope analyses of all substances can be expressed relative to VSMOW or VPDB (Vienna Peedee belemnite) on scales normalized such that the δ18O of SLAP is −55.5% relative to VSMOW. H3+ contribution in hydrogen isotope ratio analysis can be easily determined using two...
Authors
T.B. Coplen
Two-million-year record of deuterium depletion in Great Basin ground waters Two-million-year record of deuterium depletion in Great Basin ground waters
Fluid inclusions in uranium series-dated calcitic veins from the southern Great Basin record a reduction of 40 per mil in the deuterium content of groundwater recharge during the Pleistocene. This variation is tentatively attributed to major uplift of the Sierra Nevada Range and the Transverse Ranges during this epoch with attendant increasing orographic depletion of deuterium from...
Authors
Isaac J. Winograd, Barney J. Szabo, Tyler B. Coplen, A.C. Riggs, Peter T. Kolesar
Multisample conversion of water to hydrogen by zinc for stable isotope determination Multisample conversion of water to hydrogen by zinc for stable isotope determination
Two techniques for the conversion of water to hydrogen for stable isotope ratio determination have been developed that are especially suited for automated multisample analysis. Both procedures involve reaction of zinc shot with a water sample at 450 ??C. in one method designed for water samples in bottles, the water is put in capillaries and is reduced by zinc in reaction vessels...
Authors
C. Kendall, T.B. Coplen
Oxygen and hydrogen stable isotope measurements of ground waters for the central west side of the San Joaquin Valley, California Oxygen and hydrogen stable isotope measurements of ground waters for the central west side of the San Joaquin Valley, California
No abstract available.
Authors
T.B. Coplen, Carol Kendall, G. H. Davis
A review of progress in understanding the fluid geochemistry of the Cerro Prieto geothermal system A review of progress in understanding the fluid geochemistry of the Cerro Prieto geothermal system
Fluid geochemistry has played a major role in our present understanding of the Cerro Prieto geothermal system. Fluid chemical and isotopic compositions have been used to indicate the origin of water, salts and gases, original subsurface temperature and fluid flow, fluid-production mechanisms, and production-induced aquifer boiling and cold-water entry. The extensive geochemical data and
Authors
A.H. Truesdell, N.L. Nehring, J. M. Thompson, C. J. Janik, T.B. Coplen
Comment on the International Atomic Energy Agency Report on the Advisory Group Meeting on Stable Isotope Reference Samples for Geochemical and Hydrological Investigation, Vienna, Austria, September 19-21, 1983 Comment on the International Atomic Energy Agency Report on the Advisory Group Meeting on Stable Isotope Reference Samples for Geochemical and Hydrological Investigation, Vienna, Austria, September 19-21, 1983
According to U.S. Geological Survey records, a report prepared by R. Gonfiantini summarizing the findings and recommendations of the 1983 Advisory Group Meeting on Stable Isotope Reference Samples for Geochemical and Hydrologic Investigations held in Vienna does not accurately represent the consultants ' consensus on three important points. The consultants (1) recommended no value for...
Authors
T.B. Coplen, Irving Friedman, J. R. O’Neil
Science and Products
Filter Total Items: 18
No Result Found
Filter Total Items: 153
Continuous 500,000-year climate record from vein calcite in Devils Hole, Nevada Continuous 500,000-year climate record from vein calcite in Devils Hole, Nevada
Oxygen-18 (δ18O) variations in a 36-centimeter-long core (DH-11) of vein calcite from Devils Hole, Nevada, yield an uninterrupted 500,000-year paleotemperature record that closely mimics all major features in the Vostok (Antarctica) paleotemperature and marine δ18O ice-volume records. The chronology for this continental record is based on 21 replicated mass-spectrometric uranium-series...
Authors
I.J. Winograd, T.B. Coplen, J.M. Landwehr, A.C. Riggs, Kenneth R. Ludwig, Barney J. Szabo, Peter T. Kolesar, K.M. Revesz
Reporting of nitrogen-isotope abundances (Technical Report) Reporting of nitrogen-isotope abundances (Technical Report)
To eliminate possible confusion in the reporting of nitrogen-isotope analyses, the Commission on Atomic Weights and Isotopic Abundances recommends that the value 272 be employed for the 14N/15N value of N2 in air for calculating atom percent 15N from measured δ15N values.
Authors
Tyler B. Coplen, H.R. Krouse, J.K. Bohlke
Improvements in the gaseous hydrogen-water equilibration technique for hydrogen isotope ratio analysis Improvements in the gaseous hydrogen-water equilibration technique for hydrogen isotope ratio analysis
Improved precision in the H2-H2O equilibration method for δD analysis has been achieved in an automated system. Reduction in 1-σ standard deviation of a single mass-spectrometer analysis to 1.3‰ is achieved by (1) bonding catalyst to glass rods and assigning use to specific equilibration chambers to monitor performance of catalyst, (2) improving the apparatus design, and (3) reducing the...
Authors
T.B. Coplen, J. D. Wildman, J. Chen
Caution on the use of Viton® or FETFE® O-rings in carbon dioxide sample containers for δ180 analysis Caution on the use of Viton® or FETFE® O-rings in carbon dioxide sample containers for δ180 analysis
After 10 days, 3-μmol CO2 samples in containers having glass stopcocks with Viton® or FETFE O-rings were enriched in 18O by 1.5% as a result of absorption by the elastomer; this amount of enrichment is ∼20 times greater than the precision of δ18O measurements of most laboratories. No change in 13C content was observed. Increasing the sample size to 100 μmol resulted in an 18O enrichment...
Authors
Kinga M. Revesz, Tyler B. Coplen
Gas chromatographic separation of carbon dioxide and nitrous oxide for stable isotopic analysis of carbon dioxide Gas chromatographic separation of carbon dioxide and nitrous oxide for stable isotopic analysis of carbon dioxide
No abstract available.
Authors
Kinga Revesz, Tyler B. Coplen
A 250,000-year climatic record from Great Basin vein calcite: Implications for Milankovitch theory A 250,000-year climatic record from Great Basin vein calcite: Implications for Milankovitch theory
A continuous record of oxygen-18 (δ18O) variations in the continental hydrosphere during the middle-to-late Pleistocene has been obtained from a uranium-series dated calcitic vein in the southern Great Basin. The vein was deposited from ground water that moved through Devils Hole—an open fault zone at Ash Meadows, Nevada—between 50 and 310 ka (thousand years ago). The configuration of...
Authors
Isaac J. Winograd, Tyler B. Coplen, Barney J. Szabo, Alan C. Riggs
Normalization of oxygen and hydrogen isotope data Normalization of oxygen and hydrogen isotope data
To resolve confusion due to expression of isotopic data from different laboratories on non-corresponding scales, oxygen isotope analyses of all substances can be expressed relative to VSMOW or VPDB (Vienna Peedee belemnite) on scales normalized such that the δ18O of SLAP is −55.5% relative to VSMOW. H3+ contribution in hydrogen isotope ratio analysis can be easily determined using two...
Authors
T.B. Coplen
Two-million-year record of deuterium depletion in Great Basin ground waters Two-million-year record of deuterium depletion in Great Basin ground waters
Fluid inclusions in uranium series-dated calcitic veins from the southern Great Basin record a reduction of 40 per mil in the deuterium content of groundwater recharge during the Pleistocene. This variation is tentatively attributed to major uplift of the Sierra Nevada Range and the Transverse Ranges during this epoch with attendant increasing orographic depletion of deuterium from...
Authors
Isaac J. Winograd, Barney J. Szabo, Tyler B. Coplen, A.C. Riggs, Peter T. Kolesar
Multisample conversion of water to hydrogen by zinc for stable isotope determination Multisample conversion of water to hydrogen by zinc for stable isotope determination
Two techniques for the conversion of water to hydrogen for stable isotope ratio determination have been developed that are especially suited for automated multisample analysis. Both procedures involve reaction of zinc shot with a water sample at 450 ??C. in one method designed for water samples in bottles, the water is put in capillaries and is reduced by zinc in reaction vessels...
Authors
C. Kendall, T.B. Coplen
Oxygen and hydrogen stable isotope measurements of ground waters for the central west side of the San Joaquin Valley, California Oxygen and hydrogen stable isotope measurements of ground waters for the central west side of the San Joaquin Valley, California
No abstract available.
Authors
T.B. Coplen, Carol Kendall, G. H. Davis
A review of progress in understanding the fluid geochemistry of the Cerro Prieto geothermal system A review of progress in understanding the fluid geochemistry of the Cerro Prieto geothermal system
Fluid geochemistry has played a major role in our present understanding of the Cerro Prieto geothermal system. Fluid chemical and isotopic compositions have been used to indicate the origin of water, salts and gases, original subsurface temperature and fluid flow, fluid-production mechanisms, and production-induced aquifer boiling and cold-water entry. The extensive geochemical data and
Authors
A.H. Truesdell, N.L. Nehring, J. M. Thompson, C. J. Janik, T.B. Coplen
Comment on the International Atomic Energy Agency Report on the Advisory Group Meeting on Stable Isotope Reference Samples for Geochemical and Hydrological Investigation, Vienna, Austria, September 19-21, 1983 Comment on the International Atomic Energy Agency Report on the Advisory Group Meeting on Stable Isotope Reference Samples for Geochemical and Hydrological Investigation, Vienna, Austria, September 19-21, 1983
According to U.S. Geological Survey records, a report prepared by R. Gonfiantini summarizing the findings and recommendations of the 1983 Advisory Group Meeting on Stable Isotope Reference Samples for Geochemical and Hydrologic Investigations held in Vienna does not accurately represent the consultants ' consensus on three important points. The consultants (1) recommended no value for...
Authors
T.B. Coplen, Irving Friedman, J. R. O’Neil
*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