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Reston Stable Isotope Laboratory (RSIL)

Director: Tyler B. Coplen

    Lead Scientists:
    Tyler B. Coplen [Isotope Fractionation in Hydrologic Systems]
    J.K. Böhlke [Isotope Hydrology and Biogeochemistry]
    Karl B. Haase [Dissolved Gases and Environmental Tracers]

  Tyler Coplen adjusting the vacuum line.
Tyler Coplen, adjusting high vacuum line, Reston Stable Isotope Laboratory, USGS National Center, Reston, VA, USA

  Stan Mroczkowski and Janet Hannon leading Science Camp at USGS National Center.
Stan Mroczkowski and Janet Hannon leading Science Camp at USGS National Center, Reston, VA, USA
  Noble gas prep line
Noble gas sample preparation line and Helix SFT noble gas mass spectrometer
  Kinga Revesz collecting samples in the field.
Kinga Revesz, sampling for water isotopes, NAWC field site, Trenton, NJ, USA

The Reston Stable Isotope Laboratory (RSIL) produces hydrogen, carbon, nitrogen, oxygen, and sulfur stable isotope ratio analyses of water, rock, and biological samples for the operational and research components of the U.S. Geological Survey, other Bureaus of the Department of the Interior, other federal agencies, state agencies, county agencies, and organizations outside the United States. The RSIL provides isotopic calibrations services and materials worldwide. Members of the RSIL also conduct research on the use of isotope-ratio measurements in studies of water resources and environmental quality. One objective of the RSIL is to develop new techniques for isotopic analysis of oxygen-, sulfur-, carbon-, hydrogen-, and nitrogen- bearing materials. New analytical techniques expand the range of tools available for studying the movement of those elements in hydrologic and biogeochemical systems. Another objective of the RSIL is to test new applications of isotope measurements in specific field settings. Field studies of isotope behavior have contributed to understanding water-supply sustainability, ground-water/surface-water interactions, paleoclimate history, biologic cycling of nutrients, ground-water contamination, and natural remediation. This project also contributes to the improvement of measurement science and the development of isotope databases, as well as providing isotope analyses on a routine basis to a large user community both within and outside of the USGS.

Noble gases are a suite of chemically inert elements that are universally present at trace levels in air and water on earth. As their concentrations are not modified by chemical reactions or microbial activity, they are power indicators of physical processes, including temperature of recharge, gas exchange, diffusion, and transport phenomena. By measuring their concentrations and isotope ratios, we can infer groundwater residence time, recharge temperature, recharge conditions, and gas diffusion processes in the subsurface.