USGS-GD-Scientific Capabilities -  40ARGON/39ARGON Equipment




  • MAP 215 Rare-Gas Mass Spectrometer, was purchased in 1986 and put into operation in October, 1987. This instrument is the prototype of a series of modern high-sensitivity argon (rare-gas) mass spectrometers manufactured by Mass Analyzer Products in England for the analysis of small samples. Five isotopes of argon (40Ar through 36Ar) are routinely measured and the data are collected and reduced on-line by computer. Attached to the mass spectrometer is a manually operated argon-extraction system that includes a low-blank resistance furnace with furnace-temperature controller for step-wise temperature degassing of samples. Multiple samples are loaded into the furnace apparatus and each is step-heated to remove argon for analysis in the mass spectrometer. The processing of samples is done manually requiring continual supervision during the course of analysis, approximately 6-12 hours per sample. This instrument will become fully automated with improvements in the inlet/sample handling system. Located in Denver.
  • VG1200 Argon Gas Mass Spectrometer, relocated from Reston to Denver in 1996, is a high resolution rare gas machine capable of routine precision work on both 40Ar/39Ar and K-Ar, and larger samples as required for isotopic spikes and standards certification. Instrument is fully automated. Located in Denver.
  • MAP 216 Argon Gas Mass Spectrometer, relocated from Reston to Denver in 1996. This instrument is engineered throughout for ultra-low blank operation, with a special low-blank furnace for sample fusion, and a UV laser for microbeam in-situ analyses. Ages as young as <10,000 years are possible given optimal sample material. Instrument is fully automated. Located in Denver.
  • MAP 215-50 Noble Gas Mass Spectrometer, has been purchased and is scheduled for delivery in summer 1997. Given the adequate capacity for argon geochronology, this instrument will be configured for noble gas analyses; specifically 3He/4He, and 3He/21Ne as well as krypton and xenon rare gas isotopic studies. Emphasis is on strengthening the Quaternary geochronology (water and surface exposure ages) and water/rock isotopic tracer capabilities in support of Programs. Located in Denver.

     | Capabilities |
    | Geochronology, Geochemistry, and Tracer Studies  |
    | Geochronology  |