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Frederick A. Sutton Building

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Welcome to the Dissolved and Noble Gas Lab

Our research and services at the Dissolved and Noble Gas Lab are based on the use of noble gases and anthropogenic tracers to determine groundwater recharge ages and recharge temperatures, cosmogenic surface dating, and aquitard permeability. We have two facilities here at the University of Utah in Salt Lake City, Utah: the Noble Gas Lab and the Environmental Tracers Lab. The Noble Gas lab contains a mass spectrometer system capable of precise isotopic measurements of the noble gases as well as most other common atmospheric gases. The Environmental Tracers Lab utilizes a gas chromatography system for precise measurements of dissolved CFC's in natural waters to determine timing of recharge.

For more information about our facilities and methods, please see the subheading under Our Lab at the left. For pricing, please see the Services & Pricing page. For collection techniques, see the How-to page.

Tritium/Helium-3 Dating

The Dissolved and Noble Gas Lab primarily carries out groundwater age dating by measuring the concentrations of helium-3 (3He), a rare stable isotope, and tritium (3H), a radioactive isotope of hydrogen. Atmospheric atomic bomb testing in the 1950's and 60's bolstered the concentration of tritium in the atmosphere where it can become incorporated into a water molecule and enter the water cycle. During precipitation events this tritiated water enters groundwater and can be used as a dating tool for recharge.

Tritium decays to the stable isotope helium-3, which stays dissolved in the water below the water table. With precise measurement, the parent and daughter isotopes can be quantified, providing a means to accurately date when water was recharged.

If you would like to know more about tritium/helium-3 dating, see the Tritium page, and for more information about helium and other noble gases, see the Dissolved & Noble Gas page.

Chlorofluorocarbons

CFC’s are a manmade organic compound utilized for a wide range of industrial and domestic purposes, such as refrigerants and propellants. This use has resulted in large atmospheric releases of CFC gases over the last 50 years.

Thanks to precise, global, atmospheric CFC measurements beginning in 1978 as a part of the Atmospheric Lifetime Experiment, there is an excellent recorded record of global CFC concentrations. Precisely measuring the concentration of CFC's dissolved in groundwater samples. The date of recharge can be determined using the atmospheric CFC records.

For more information about the use of chlorofluorocarbons for dating, see the Chlorofluorocarbons page.

Rock Dating and Permeability

The measurement of cosmogenic helium makes it possible to date rocks. Not the date of rock formation, but dating how long a rock has sat at the Earth's surface and been exposed to cosmogenic radiation. The bombardment of the earth by particles causes spallation within the atmosphere, and within the upper centimeters of terrestrial surfaces. Longer exposures to radiation increases amounts of helium-3 among other cosmogenic isotopes.

Helium analysis also has the potential to help solve the world's CO2 problems. If aquitards have very low permeability, the 4He produced by Uranium series decay should still be in place, and not been flushed through by waters over millennia. If the aquitards are tight enough, CO2 injection should be a permanent solution.