Home , Go Back to faculty page MARC M. HIRSCHMANN Professor PhD, 1992, University of Washington Research Group Web Page: Experimental Petrology Laboratory Office: 220 Pillsbury Hall Phone: (612) 625-6698 Fax: (612) 625-3819 Email: hirsc022@... Personal Web page: http://www.geo.umn.edu/people/profs/hirsc022/Hirschmann.html

    I am interested in applying geochemistry and experimental petrology to problems related to igneous petrogenesis, with a particular emphasis on understanding mantle melting processes. Several research projects employ high temperature, high pressure experimental techniques using a piston cylinder laboratory installed in 1998. Complementary to the experimental studies are calibration and application of thermodynamic models for mantle minerals and silicate liquids using the MELTS thermodynamic algorithm. Other interests include application of U-series daughter products to understanding melting processes, petrogenesis of layered intrusions, order/disorder and crystal chemistry of rock-forming silicates.

    One active research area is experimental study of the role of mantle heterogeneities (such as layers or veins of pyroxenite or metasomatized peridotite) in basalt petrogenesis. Such heterogeneities are widely thought to play a role in formation of some basalts, but much is not known about the melting behavior of these exotic lithologies. For example, solidus temperatures, the composition of partial melts formed by these rocks, and the ability of melts to segregate from pyroxenite or garnet pyroxenite source rocks have not been determined.

    Another important part of my research program is the application and refinement of thermodynamic calculations for understanding mantle melting processes. Thermodynamic modeling of mantle melting and of other igneous processes is a powerful tool for gaining insight into petrologic phenomenon, and we have applied such calculations to better understand such problems as the near-solidus composition of partial melts of peridotite, the effect of peridotite composition on the composition of partial melts, and variations in melt production during mantle melting owing to differences in mantle composition and/or mantle dynamics. However, the thermodynamic models used to make these calculations are imperfect, and we are presently conducting experiments and revising our models in order to improve our ability to make such calculations.

    A new direction initiated recently in collaboration with Larry Edwards and graduate student Rebecca Thomas is study of mantle melting processes beneath the volcanoes of the Central American arc using 231Pa, a short-lived daughter product of 235U. Since 231Pa concentrations in young volcanic rocks are sensitive indicators of the timing and style of melt extraction in mantle source regions, this study promises to provide a new understanding of the melting process beneath arc volcanoes.

• 2004, Fellow, Mineralogical Society of America

• Dynamic Earth: An Introduction to Geology
• Planets of the Solar System
• Mineralogy
• X-ray diffracton workshop
• Igneous Petrology

• Dasgupta, R. Hirschmann, M.M. and Dellas, N. (2005) The effect of bulk composition on the solidus of carbonated eclogite from partial melting experiments at 3 GPa. Contributions to Mineralogy and Petrology 149:288-305.
• Allwardt, J.R., Stebbins, J.F., Schmidt, B.C., Frost, D.J., Withers, A.C., Hirschmann, M.M. (2005) Aluminum coordination and density in high-pressure aluminosilicate glasses: Significance for the structural changes and densification in basaltic magmas. American Mineralogist 90: 1218-1222.
• Hirschmann, M.M. Aubaud, C. and Withers, A.C. (2005) Storage capacity of H₂O in nominally anhydrous minerals in the upper mantle Earth and Planetary Science Letters. 236: 167-181.
• Kogiso, T. Hirschmann, M.M., Reiners, P.W. (2004) Length scales of mantle heterogeneities constrained by basalt geochemistry. Geochimica et Cosmochimica Acta 68: 345-360.
• Pertermann, M., Hirschmann, M. M., Hametner, K. D. Günther, M.Schmidt (2004) Experimental determination of trace element partitioning between garnet and silica-rich liquid during anhydrous partial melting of eclogite. Geochemistry, Geophysics, Geosystems. V5, Q05A01, doi:10.1029/2003GC000638.
• Kogiso, T., Hirschmann, M.M. and Pertermann, M. (2004) High pressure partial melting of mafic lithologies in the mantle. Journal of Petrology 45: 2407-2422. doi:10.1093/petrology/egh057.
• Dasgupta, R. Hirschmann, M.M. and Withers, A.W. (2004) Deep global cycling of carbon constrained by the solidus of anhydrous, carbonated eclogite. Earth and Planetary Science Letters 227: 73-85 doi:10.1016/j.epsl.2004.08.004
• Aubaud, C., Hauri, E.H. and Hirschmann, M.M. (2004) Water partition coefficients between nominally anhydrous minerals and basaltic melts. Geophys. Res. Lett. 31, L20611 d01:10.1029/2004GL02134
• Pertermann, M. and Hirschmann, M.M. (2003) Partial melting behavior of MORB-like pyroxenite and implications for the role of garnet during basalt petrogenesis. Journal of Geophysical Research 108 [B2] 10.1029/2000JB000118.
• Koga, K. Hauri, E., Hirschmann, M. and Bell, D. (2003) Hydrogen concentration analyses using SIMS and FTIR: Comparison and calibration for nominally anhydrous minerals. Geochemistry, Geophysics, Geosystems V4 1019, doi:10.1029/2002GC000378.
• Hirschmann, M.M., Kogiso, T. Baker, M.B., and Stolper, E.M. (2003) Alkalic magmas generated by partial melting of garnet pyroxenite. Geology 31:481-484.
• Pertermann, M., and Hirschmann, M.M. (2003) Anhydrous partial melting experiments on MORB-like eclogite: phase relations, phase compositions and mineral/melt partitioning of major elements at 2-3 GPa. Journal of Petrology 44: 2173-2201.
• Kogiso, T., Hirschmann, M.M., and Frost, D.J. (2003) High pressure partial melting of garnet pyroxenite: possible mafic lithologies in the source of ocean island basalts. Earth and Planetary Science Letters 216: 603-617.

• National Science Foundation-Earth Sciences Partial melting of carbonated peridotite and eclogite in the upper mantle. 7/01/03-6/31/06 (with A.W. Withers)
• National Science Foundation- CSEDI (Collaborative Studies of the Earth's Deep Interior) CSEDI:Collaborative Research: Experimental and SIMS investigation of H₂O storage capacity of the mantle 5/1/05-4/30/07 (with A.W. Withers)
• National Science Foundation - Earth Sciences "Collaborative Research: A new experimental database for improving and extending MELTS" January 1, 2005-December 31, 2006
• National Science Foundation-Earth Sciences REU Site: Fluids in the Earth from surface to core, 4/15/03-03/31/06 (with E. Ito)
• National Science Foundation - Earth Sciences "Chemistry and Structure of Grain and Phase Boundaries: Importance for Trace Element Storage and Transport in the Mantle 07/01/04-06/30/07 (with D.L. Kohlstedt).