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Mineralogy Faculty Profiles
Many research directions in the area of mineralogy are represented by the IU Earth and Atmospheric Sciences faculty. Click on names to connect to individual home pages for more detailed information on research and complete lists of publications:
Herman B. Wells Professor of Geological Sciences. Provenance of siliciclastic sediments in terrestrial planetary bodies.
Petrologic evolution of planetary crusts through the study of surface materials on the Earth and the Moon, with the ultimate goal of reconstructing the geology of that part of a planetary crust which has been eroded to give rise to a body of sediment. Current research includes evolution of the lunar regolith, modeling diagenesis of volcaniclastic sediments of Mars, and extraterrestrial remote sensing research to provide a mineralogic-petrologic calibration of spectral reflectance of rocky planetary bodies.
Professor of Geological Sciences and Haydn Murray Chair of Applied Clay Mineralogy. Surface properties, crystallography and geochemistry of clay minerals. Applications of clay and zeolite minerals and interactions with organic pollutants. Rheology of clay suspensions.
Research on the application of crystal chemical and crystal structural fundamentals to geological, materials, and environmental (including extraterrestrial) problems. These problems are approached using a combination of experimental (X-ray and neutron powder diffraction, thermoanalytical methods) and theoretical methods. Research is centered in several broad areas, including (1) Structures, properties, and origins of fine-grained minerals, such as clay minerals and natural zeolites; (2) X-ray and neutron powder diffraction, including quantitative analysis and Rietveld analysis; (3) Behavior of minerals under controlled temperature and water-pressure conditions, including study of clays and zeolites under controlled-T, -P(H2O) conditions has the potential to provide much new information on mineral behavior and phase transitions. Such experiments routinely provide new insights into the structures and behavior of materials that analyses under room conditions do not provide. These experiments are particularly important in understanding and predicting applications of minerals under real-world conditions because many minerals are used under conditions quite distinct from typical laboratory conditions of T and P(H2O). An example of these studies is my research on the thermal and sorptive behavior of minerals at the potential high-level radioactive waste repository at Yucca Mountain, Nevada. This work included X-ray diffraction under non-ambient conditions and emphasized the effects of long-term heating of a variety of minerals, including clays and zeolites. I recently combined this research with thermodynamic modeling to provide insights into the coupled effects of temperature and water vapor pressure on mineral stability.
Professor of Geological Sciences and Director of Undergraduate Studies. Chemical and physical processes of magmatic crystallization and differentiation. Origin and geochemistry of layered intrusions and lavas. Experimental petrology.
Research interests are in the areas of igneous petrology and volcanology. He is involved in experimental studies relating to metal solubility in mafic magmas and the distribution of metals between alloys, sulfide minerals, silicate minerals, and melt.
Professor of Geological Sciences. Genesis of metallic ore deposits. Applications of stable isotopic geochemistry in petrology. Igneous and hydrothermal processes on metals. Thermodynamic/kinetic modeling.
Ore genesis and stable isotope geochemistry. Role of organic matter in metal enrichment within black shales and both hydrothermal and magmatic ore deposits. Role of organic activity in mediating sulfur isotopic distribution in sedimentary rocks and their metamorphosed equivalents.
Professor of Geological Sciences. Early diagenetic mineral formation in shales. Preservation of microbes in mudstones. Provenance of quartz in mudstones.
Shales are my passion. Broadly speaking, my main research interest is the geology of shales and mudstones. These fine-grained rocks constitute approximately two thirds of the sedimentary column, and are nonetheless the least understood sedimentary rock type. The lion's share of the sedimentary rock record consists of shales and mudstones. Although still only a footnote in most soft rock curricula, there are a number of very good reasons to study shales and mudstones. First, in order to read the rock record correctly and at the highest detail possible, we have to learn how to "read" shales. Second, regardless whether they contain a fraction of a percent or several ten percent of organic matter, mudstones and shales are the source of the hydrocarbons that fuel the world economy. Third, the seals that keep hydrocarbons in their reservoir, protect groundwater resources, and contain dangerous industrial waste products are all made of the same stuff - shales and mudstones. Recent funding success is making it possible now to pursue sophisticated petrographic studies by means of a state of the art environmental SEM, and experimental sedimentology with a flume specifically designed for working with muds. Go to my research web site to find out more about the kind of work I am involved in.
Assistant Professor of Geological Sciences. Biogeochemistry of Metals.
I am a biogeochemist investigating metal chemistry in the Earth’s lithosphere, hydrosphere, and biosphere. Specifically I examine stable isotope fractionation of transition and post–transition metals in order to develop new tools for tracing chemical reactions that involve metals.
My primary focus is on fundamental, experimental investigations of metal isotope fractionation mechanisms. In the past ten years multi–collector ICP mass spectrometry has led to the discovery that stable isotopes of most metals fractionate in a wide range of environments all over the Earth. The number of published metal isotope analyses is burgeoning rapidly, and the prospect of much new understanding of metal chemistry in nature is exciting. Few investigators, however, have yet attempted to elucidate the mechanisms that drive metal isotope fractionation. Without careful investigation of molecular–scale mechanisms and systematics of metal isotope effects, we cannot hope to interpret robustly the wealth of information available in nature. SesameLab website
Professor of Geological Sciences. Metamorphic petrology, structural petrology, tectonic, geochronology.
Laboratory and field studies of several aspects of metamorphic geology, from diagenesis and low grade metamorphism in slaty rocks to high grade metamorphism and partial melting. Much of this research focuses on identifying the relationships between deformational and metamorphic processes, from the grain scale and pressure solution to the scale of terranes and terrane assembly. Chemical processes turn out to have a relatively large role in the evolution of fault rocks, from pressure solution-like dissolution/precipitation reactions in a near closed system, to reaction softening and reaction hardening in relatively open systems. We have identified ductile processes in very shallow fault zones where brittle deformation is expected, and evidence for brittle (seismic?) deformation in rocks as high grade as the sillimanite zone, where ductile deformation is expected. We have been working on fault rocks from the Moine thrust, Scotland, Insubric line southern Swiss Alps, and the northern and central Appalachians.