National Research Program | Isotope Tracers Project

USGS Isotope Tracers Project

The Menlo Park Stable Isotope Lab (MPSIL) is a research lab focused on applying stable isotope techniques to investigate water quality and ecological problems. The purpose of the “Isotope Tracers” research project is to develop new isotope methods and applications to solve problems of national importance.

The main research focus of the group is tracing sources of nutrients and organics and studying biogeochemical processes in aquatic ecosystems, with projects ranging from small forested catchments to large rivers like the Mississippi and large wetlands like the Everglades. Several recent projects are aimed at understanding nutrient sources and processing in the San Francisco Bay and Delta. Other interests of the group include determining causes of hypoxia in riverine and coastal ecosystems, foodweb reconstructions, tracing anthropogenic nitrate sources to the atmosphere, runoff mechanisms in small catchments, and age-dating ground waters.

Stable Isotope Lab

Major analytical instrumentation includes four mass spectrometers with a range of peripherals, capable of analyzing C, N, O, H, S, Cl, and Br isotopes in a wide variety of natural materials, including organic matter, gases, and minerals. Water isotopes are analyzed using a laser spectrophotometer.

Contact:

  • Carol Kendall (ckendall@usgs.gov)
  • Steve Silva (srsilva@usgs.gov)

Tritium Lab

The Tritium Lab has facilities for extraction of tritium from waters by distillation and electrolysis, as well as four liquid scintillation counters for analysis of 3H and 35S.


Contact:

  • Megan Young (mbyoung@usgs.gov)
  • Doug Choy (dchoy@usgs.gov)

Project Contacts:

  • Carol Kendall
    U.S. Geological Survey
    345 Middlefield Rd, MS 434
    Menlo Park, CA 94025
    ckendall@usgs.gov
    650-329-4576

  • Megan Young
    U.S. Geological Survey
    345 Middlefield Rd, MS 434
    Menlo Park, CA 94025
    mbyoung@usgs.gov
    650-329-4544

  • Steve Silva
    U.S. Geological Survey
    345 Middlefield Rd, MS 434
    Menlo Park, CA 94025
    srsilva@usgs.gov
    650-329-4538