Facilities - University of Wisconsin-Madison, Department of Geology & Geophysics
Radiogenic Isotope Laboratory
The laboratory consists of a 500 square foot instrument room (climate controlled and all incoming air is HEPA filtered) that contains a (2000) multi-collector inductively-coupled plasma mass spectrometer (a Micromass IsoProbe) and a thermal ionization mass spectrometer (a VG Instruments Sector 54).
 In a separate 900 square foot room are clean room facilities for sample preparation. This clean room was remodeled in spring 2005 and expanded. The new clean room consists of laboratories with casework and fume hoods made of polypropylene. The laboratory routinely produces high-precision Fe, Cu, Th, Rb/Sr, Sm/Nd, Lu/Hf, and U/Pb isotope and isotope dilution analyses, including the REEs. The laboratory is supervised by Professor Clark Johnson and Dr. Brian Beard.
Stable Isotope Laboratory
The light Stable Isotope Lab includes two Finnigan 251 5-collector gas-source mass-spectrometers, and two laser systems for fluorination and analysis of oxygen isotopes in silicates, oxides, phosphates, and carbonates with sample sizes down to 100 microgram. We currently analyze 30-40 silicate samples in an 8-12 hour day. Since 1994, the lab has averaged up to 3000 silicate analyses per year by laser with average daily precision of ±0.07‰ and accuracy of ±0.1‰ relative to VSMOW. An air-lock sample chamber permits analysis of finely ground powders and other reactive materials by laser without problems of pre-reaction. Samples are analyzed as either CO2 or O2 and all three oxygen isotopes can be accurately analyzed for studies of mass-dependent and independent processes. Other extraction lines permit analysis of D/H in minerals and water; carbon isotopes in carbonates, organic matter and diamond; oxygen isotopes in carbonates and water; and sulfur isotopes in sulfides. The laboratory is supervised by Professor John Valley and Mr. Mike Spicuzza.
WiscSIMS-Ion Microprobe Laboratory
The ion microprobe lab houses a new (March 2005) large radius multi-collector CAMECA IMS-1280 ion microprobe. This instrument has a total of 10 electron multiplier and Faraday cup detectors, which can be used up to five at a time for simultaneous analysis of elemental composition or isotope ratio.
 Spot size for in situ analysis of thin sections and grain mounts ranges from 250nm to 25μm. The 1280 has a number of improvements over earlier 1270 instruments, several of which are designed to enhance precision of isotope ratio analysis, including: better focusing of the primary and secondary beam, continuous monitoring of primary beam current during analysis, better control of external magnetic fields in the sample chamber and mass-spectrometer, NMR control of analyzer magnet, oil-free rough pumping for cleaner vacuum, all digital electronics and new PC computer control. Imaging is possible with a static beam using the instrument's capabilities as an ion microscope or by scanning ion techniques. This lab is dedicated to achieving the best possible accuracy and precision in stable isotope ratio measurements with emphasis on: O, C, S, H, N, Li, B, Si, Mg, Ca, and Fe. The laboratory is supervised by Professor John Valley and Dr. Noriko Kita.
Geomicrobiology Laboratory
This new laboratory occupies ca. 1500 square feet in a new wing of Weeks Hall at UW-Madison. The laboratory is equipped for handling geological materials and microorganisms, in particular the culturing and manipulation of various kinds of respiratory and lithotrophic bacteria. Equipment relevant to this project includes: autoclave; lyophilizer; analytical balances (Denver Instruments); UV/VIS spectrophotometer; gas chromatograph with FID and TCD detectors; high-pressure liquid chromatograph with UV/VIS detector; ion chromatograph; BET Surface area analyzer; anaerobic chambers; high speed centrifuge; microcentrifuges; temperature-regulated incubators and water baths; compound phase contrast/epifluorescence microscope. The laboratory is supervised by Professor Eric Roden.
Mineralogy and Nanoparticle Analysis Laboratory
The synthesis of minerals and x-ray analysis is done in a new laboratory in a new wing of Weeks Hall, and utilizes a programmable furnace, one tube furnace, ovens, shakers, vacuum systems, pH meters, centrifuges, Parr-type digestion bombs, balances, and optical microscopes for routine mineral/materials syntheses and mineral-water interaction experiments. Optical microscope: A research grade optical microscope (Olympus BX51) with polarized light (both transmission and reflection) and UV light capabilities. The microscope is also capable of bright-field, dark-field, phase contrast, and epi-fluorescence imaging. The microscope is equipped with a high quality / sensitivity FLEX camera system (Diagnostic Instruments). Microporosimeter: a new Nova 2200e (Quantachrome Instruments) microporosimeter that can measure BET surface area, nanopore surface area, and nanopore sizes. Surface tension analysis system: A DCAT 11 (DataPhysics) system for measuring dynamic contact angle and surface / interfacial tension. The system is attached to a powder sample unit designed for measuring powder samples and nano-crystals.
X-ray Powder Diffraction Laboratory: A Sintag Pad V automated powder diffraction unit, Jade (Materials Data, Inc.) and Shadow software for data reduction and analysis. XRD patterns can be recorded using step scan mode. The obtained data can be used for quantitative analysis using the Rietveld method. The laboratory is superivsed by Professor Huifang Xu.
Computational Chemistry Laboratory
The computational chemistry equipment consists of a server powered by four AMD Opteron™ processors, which aids in the group's molecular modeling efforts. Using the Gaussian03® and Material Studio® software, we pursue both quantum-mechanical (electronic structure theory-based) and atomistic molecular modeling/molecular dynamics (MM/MD) approaches. The laboratory is supervised by Professor Nita Sahai.
Low-Temperature Geochemistry Laboratory
The wet chemistry lab-space occupied by the Prof. Sahai's Interfacial BioGeochemistry Group is used primarily as a preparatory lab for all of our group members, as well as for members of other research groups in the department.
Equipment used by the group in the lab includes a Beckman-Coulter Avanti® J-E centrifuge (capable of spinning rates up to 21,000 rpm, or 53300g), a Barnstead NANOpure Diamond™ water filtration system, Metrohm 718 STAT Titrino potentiometric titrator, a NuAire laminar flow fume hood, and glass vacuum/distillation lines. A Coy dual-chamber glove box/anaerobic chamber, allows for work in controlled atmospheres. It is equipped with an airlock chamber and oxygen monitor, and is currently used for working in nitrogen, oxygen, and mixed nitrogen/hydrogen atmospheres.
 In addition to the facilities described here and, due in large part to the interdisciplinary nature of our work, group members have formed working relationships with a number of other labs on campus. These include labs in the departments of Chemistry, Biochemistry, Water Science, Materials Science, and Soil Science, as well as other labs in our own department. Through these relationships, there is access to numerous analytical instruments and techniques, including, but not limited to, Scanning Electron and Atomic Force Microscopy (SEM and AFM), Infrared and NMR Spectrometry, Inductively-Coupled Plasma Mass Spectrometry (ICP-MS), Light Scattering, Isothermal Titration Calorimetry (ITC), and X-Ray Diffractometry (XRD). The laboratory is supervised by Professor Nita Sahai.
Electron Microprobe Laboratory
 The electron microprobe laboratory is a University-wide facility in Weeks Hall and features a Cameca SX51 instrument used to collect in situ chemical compositions and maps from selected samples at the micron scale. In addition to 5 wavelength dispersive spectrometers, the probe has a PGT energy dispersive detector, back-scattered electron and secondary electron detectors, and a cathodoluminescence photomultiplier. The laboratory is supervised by Dr. John Fournelle.
Scanning Electron Microscope Laboratory
 The Scanning Electron Microscope laboratory of the Department of Geology and Geophysics houses a new Hitachi S-3400N variable pressure SEM with special capabilities for high brightness (and color) cathodoluminescence, EBSD, EDS with spectral imaging and very high sensitivity BSE imaging. The laboratory is supervised by Dr. John Fournelle.
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