HistoryThe Arizona Noble Gases Laboratory (ANGL) has been in operation at the University of Arizona since 1990. Now under the direction of Dr. Timothy Swindle of the Lunar and Planetary Laboratory (LPL), it was originally established as a joint venture between the Geosciences and LPL. It operated that way for a decade before the departure of Prof. Suzanne Baldwin. Since then it has been very productive in the age dating of meteorites and lunar samples. In early 2007, it was re-established as a jointly operated facility with the addition of full-time researcher, Dr. Clark Isachsen, and now is roughly evenly split between isotopic analysis and age determination of extraterrestrial and terrestrial samples. This expansion of capability has been facilitated by a state-of-the-art automation upgrade to the centerpiece of the facility, a high-sensitivity VG5400 mass spectrometer and associated noble gas extraction line. Capabilities include incremental heating of samples with either a high-precision resistance heated furnace or an argon-ion laser. The predominant application of this facility is to Ar-Ar analysis for age dating purposes, but Ne, Kr, and Xe isotopes can also be determined.
40Ar/39ArThe utility of Ar-Ar thermochronology to a wide range of geological problems is well established. The method allows for accurate and precise determination of isotopic ages and thermal histories of an assortment of potassium-bearing minerals and rocks ranging from tens of thousands of years to the age of the solar system, and over a range of closure temperatures from roughly 155-550°C. Such capability is extremely beneficial to placing time constraints on geologic processes including regional tectonics studies, young volcanic stratigraphy, mineralization of ore systems, sediment provenance, time-scale calibration, rates and timing of differential uplift, age of metamorphism, and age of faulting to name a few. As such, it constitutes an integral component of the Arizona Geochronology Center (AGC).
Please contact Clark Isachsen for further information
This web site is funded through a research grant from NASA to Tim Swindle. Site images, construction, and maintainence by C. Isachsen. Contents Copyright 2008