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LinksResearch Areas:
Research AreasPetrology, High Temperature Geochemistry and Economic GeologyFaculty: M. Appold, R. Bauer, P. Nabelek, K. Shelton, A. Whittington The petrology, high-temperature geochemistry and economic geology group leads integrated field, laboratory and theoretical research to unravel several challenging sets of problems in igneous and metamorphic petrology and economic geology. Students working with these faculty have the opportunity to apply electron microprobe analysis, various major and trace element analytical techniques (including LA-ICPMS), and stable isotope methods to field-based studies in exciting localities in the United States and elsewhere. In addition, an experimental petrology lab is currently under construction that will allow students to perform melting and crystallization experiments on natural rocks or synthetic systems. One research focus of this group is the study of hydrothermal systems in a variety of crustal environments as revealed by direct analysis of fluids in fluid inclusions and by mineral phase equilibria, stable isotope ratios and other geochemical indicators in metamorphic rocks and ore deposit systems. The challenge is to understand fluid sources, fluid-flow patterns and element transport in crustal rocks that have undergone heating and recrystallization on a variety of scales from small contact aureoles, such as the Notch Peak aureole, Utah, to more regional environments, such as mesothermal gold systems in greenstone belts and carbonate-hosted Pb-Zn-Cu deposits of the midcontinent United States and Ireland. A second set of studies is aimed at unraveling histories and mountain-building processes of various orogenic terranes, including Precambrian terranes in Wyoming, South Dakota, Minnesota, Canada and Brazil, and younger terranes of the Alaskan Cordillera, coastal California, and Himalaya-Tibet. In these studies, field mapping, structural interpretations, mineral assemblages in metamorphic rocks and the petrology and geochemistry of igneous rocks are used to deduce pressure-temperature-time paths of orogenic events and the relationships among crustal deformation, heat flow, melt generation, and pluton emplacement. These studies lead to a more comprehensive understanding of mountain-building and mountain-collapsing events during construction of the North American and other continents over geologic time.
A third research focus is directed toward deducing the controlling petrologic and geochemical factors that lead to the petrogenesis of leucocratic granites and granitic pegmatites in the crust. In particular, the aim is to understand the influence of fluids and of fluid-mobile elements, such as boron and lithium, on melting of protoliths leading to highly granitic melts and the subsequent role of these components during differentiation of the magmas following emplacement. Other aspects of this research include the investigation of the role of accessory minerals during melting of source rocks on the concentrations of many trace elements, such as the rare earths, uranium, and thorium, and determining the provenance of leucogranites using isotopic methods. The long-standing field and geochemical program in this area will be enhanced by the experimental petrology lab, which will allow students and researchers to study partial melting under a range of crustal conditions. The fourth research area of this group is investigation of the physical and thermodynamic properties of magma, such as density and viscosity, and particularly the effect of dissolved volatiles such as water, since these play a major role in determining the nature of volcanic eruptions (explosive or gentle). |
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Department of Geological Sciences | 101 Geology Building | Columbia, MO 65211-1380 Department of Geological Sciences | College of Arts and Science | University of Missouri Last modified: November 2009
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