Skip to Main Content
Mobile Menu

Welcome to the Isotope Geology Laboratory!

  • Professor places samples for geochronology
    Thermal Ionization Mass Spectrometry

    Dr. James Crowley places samples for high-precision U-Pb geochronology into the IsotopX Isoprobe-T thermal ionization mass spectrometer (TIMS)

  • Chromatography experiment
    Anion exchange chromatography

    U and Pb atoms are separated from the dissolved zircon matrix via anion exchange chromatography to ensure high ion yields in high-precision isotope dilution thermal ionization mass spectrometry

  • Students learning about rock and landform relative dating
    K-12 students discover geochronology on Castle Rock

    The Castle Rock Reserve in Boise's East End provides a rich venue for teaching the fundamentals of relative dating of rocks and landforms of the Snake River Plain

  • Crushing rock in the preparation laboratory
    Mineral Separation

    Extracting zircons from a rock starts with crushing and milling in the Rock Preparation Laboratory in the new Environmental Research Building

  • Students and faculty study rock formations in Germany
    Middle Devonian strata of central Germany

    Students and faculty from Boise State, SUNY-Geneseo, the Berlin Museum, and the University of Frankenburg are collaborating on a study of Devonian chronostratigraphy

  • Isotope Geology Laboratory
    The new IGL

    The Isotope Geology Laboratory has a new home in the newly constructed Environmental Research Building, on the east side of Boise State's main campus

  • isotope dilution analysis
    Dissolution at high temperatures and pressures

    Dissolving zircon crystals at high temperatures (220°C) for isotope dilution analysis relies upon large volume Parr pressure vessels

  • High temperature annealing prepares zircon crystals for chemical abrasion
    Annealing and chemical abrasion

    High temperature annealing (900°C) prepares zircon crystals for the chemical abrasion method, an efficient partial dissolution method for removing open-system intra-crystalline domains

  • Luminescent crystals
    Zircon cathodoluminescence (CL)

    Zircon crystals are luminescent under electron beam bombardment, revealing internal growth patterns invisible to the naked eye

  • mass spectrometers in the isotope geology laboratory
    Phoenix X62

    The IGL hosts two thermal ionization mass spectrometers with state-of-the-art ion-counting and 10^12 ohm Faraday amplifiers: the new IsotopX Phoenix X62 and the upgraded IsotopX Isoprobe-T

The Boise State University Isotope Geology Laboratory (IGL) is a state-of-the-art facility for the analysis of radiogenic isotopes in Earth materials, with a focus on in situ and high-precision geochronology (U-Pb zircon) and tracer isotope geochemistry. These tools can be applied to a variety of problems in igneous and metamorphic petrology, structural geology and tectonics, paleobiological evolution and paleoclimate change in deep time.

The IGL infrastructure includes a class 10 clean laboratory, thermal ionization mass spectrometry facility, and laser ablation inductively coupled plasma mass spectrometry laboratory, along with supporting rock preparation, mineral separations, and optical & electron beam imaging laboratories in the Department of Geosciences at Boise State University. Details of the Laboratory’s construction and facilities can be found on the IGL Infrastructure page. Visit the IGL Personnel page for profiles of our researchers.

Earth Time logoThe IGL is a node in the EARTHTIME Network for the Calibration of Earth History. In the spirit of teamwork and cooperation fostered by this initiative, please take a look at our developing LABSHARE archive of analytical procedures used in the IGL for isotope geochemistry and geochronology.

Questions regarding the IGL’s capabilities and services can be referred to Dr. Mark Schmitz ( or Dr. James Crowley (

Samples can be shipped c/o Dr. Schmitz or Dr. Crowley to the address under “Contact Us”. Before shipping samples to the IGL, please complete the sample template and forward to

News & Announcements

  • Enhanced UPbR data reduction spreadsheet December 6, 2016 A more sophisticated UPbR data reduction (Schmitz and Schoene, 2007) sample template file containing enhancements like weighted mean calculation, comprehensive Th/U disequilibrium correction alternatives, outlier rejection calculations, and analysis of variance graphs is now available as BSULab_UPbR17-2_Anyone.xls.
  • “ZirChron” app updated with new sample suites June 1, 2016 We have added new suites of zircons from a variety of rhyolite tuffs and lavas to the “ZirChron” app in the Education and Outreach page.  These new samples broaden the characteristics of the zircon suites that students can experiment with, including examples with problems of crystal inheritance, and issues of LA-ICPMS versus CA-IDTIMS reproducibility.
  • New in Geology – “A newly identified Gondwanan terrane in the northern Appalachian Mountains” April 29, 2014 Mountain-building and the end of an ancient ocean beneath modern New England

See previous news items