Laboratory for Crustal Petrology
Department of Geology, University of Maryland

 Department of Geology, University of Maryland, College Park, Maryland 20742

View of 1493 m peak from Umanap Suvdlua to show upper zone in the mountain peak and the intermediate zone in the fjord wall; Qorqut Granite Complex, Greenland.

RESEARCH GOALS OF THE LABORATORY FOR CRUSTAL PETROLOGY

Research in the Laboratory for Crustal Petrology is concerned with understanding the origin and evolution of the earth's crust, which includes crust-mantle interactions and processes of recycling within the crust. In order to understand crustal recycling, faculty and students are investigating the pressure-temperature-time-deformation evolution of metamorphic belts, and the generation, segregation, transfer and emplacement of granite within the earth's crust. This work involves integration between field studies, petrology and geochemistry, utilizing additional facilities in the Isotope Geochemistry Laboratories within the Department of Geology and the Electron Microprobe Analyzer within the Center for Microanalysis.

Granite Conference, ISGAM II (Brazil), August 1997

Stromatic migmatite from southern Brittany, France. Image acquired by Cambria Denison (University of Texas, Austin). 3-D reconstruction from x-ray computed tomography. X-ray scans were 1-mm thick and 2 minutes in duration. Blue represents lower density areas of sample; yellow represents higher density areas. A leucosome (blue) that contains a ~ 3-mm garnet (yellow) can be observed in the center right of the image. Height of sample is 5 cm.

Ph.D. - Gary S. Solar

M.A., 1994, Temple University, Philadelphia, PA.

B.S., 1992, Temple University, Philadelphia, PA.

Phone: (301) 405-6964
FAX:   (301) 314-9661
solar@geol.umd.edu

 Ph.D. research: My focus has been to understand better the processes and mechanisms by which granitic melt is transfered through the crust from source to emplacement. I have been studying this process using an integration of field and laboratory work, based on the metamorphic and migmatitic rocks of the Tumbledown Mountain area, west-central Maine (Central Maine Belt, 7 km N of Rumford, Maine). This region features a migmatite domain juxtaposed reversely with non-anatectic rocks of amphibolite facies via km-scale zones of high strain. Larger bodies of granite are located in relatively low strain areas inbetween.

Geochemical, including Sr and Nd isotope tracers, and U-Pb and Rb-Sr geochronological methods are being used to examine the viability of correlations between granite plutons and migmatite leucosomes based on field relations.

M.S. - Jinmei Tian

Phone: (301) 405-4378
Fax:   (301) 314-9661
jinmei@geol.umd.edu

 M.S. research:

Burgess, J.L., Metamorphic studies in the Port aux Basques Area, SW Newfoundland, Canada.  Awarded M.S. in 1994

Pressley, R.A., Petrogenesis of the Phillips pluton, west-central Maine. Awarded M.S. in 1997.
 

Brown, M. and Solar, G.S., 1999. Observations on the mechanism of syntectonic ascent and emplacement of granite magma in an obliquely convergent (transpressive) orogen. Tectonophysics (in review).

Brown, M. and Pressley, R.A., 1999. Crustal melting in nature: Prosecuting source processes. Physics and Chemistry of the Earth, 00, 000-000.

Solar, G.S. and Brown, M., 1999. The classic high-T — low-P metamorphism of west-central Maine, USA: Is it post-tectonic or syn-tectonic? Evidence from porphyroblast-matrix relations. Canadian Mineralogist, 00, 000-000.

Pressley, R.A. and Brown, M., 1998. The Phillips Pluton, Maine, USA: Evidence of heterogeneous crustal sources, and implications for granite ascent and emplacement mechanisms in convergent orogens.  Lithos, 00, 000-000.

Brown, M. and Solar, G.S., 1998. Granite ascent and emplacement in contractional orogenic belts. Journal of Structural Geology, 00, 000-000.

Solar, G.S., Pressley, R.A., Brown, M. and Tucker, R.D., 1998. Granite ascent in convergent orogenic belts: testing a model. Geology, 26, 711-714.

Brown, M., 1998. Ridge-trench interactions and high-T — low-P metamorphism, with particular reference to the Cretaceous evolution of the Japanese Islands. In: Treloar, P.J. and O'Brien, P.J. (eds) What controls metamorphism and metamorphic reactions. Geological Society Special Publication No. 138, 131-163.

Brown, M. and Solar, G.S., 1998. Shear zone systems and melts: Feedback relations and self-organization in orogenic belts. Journal of Structural Geology, 20, 211-227.

  Brown, M., 1998. Unpairing metamorphic belts: P-T paths and a tectonic model for the Ryoke Belt, southwest Japan. Journal of Metamorphic Geology, 16, 3-22.

Brown, M. and O'Brien, P.J., 1997. Evolution of Metamorphic Belts: A Changing View.  In: Xianglin, Q., Zhendong, Y. and Hall, H.C. (Eds.), Precambrian Geology and Metamorphic Petrology, Proceedings of the 30th International Geological Congress, VSP, Zeist, The Netherlands, V. 17, 217-231.

Brown, M., 1997. Migmatites and Melt Migration. In: Xianglin, Q., Zhendong, Y. and Hall, H.C. (Eds.) Precambrian Geology and Metamorphic Petrology, Proceedings of the 30th International Geological Congress, VSP, Zeist, The Netherlands, V. 17, 187-202.

Raith, M., Karmakar, S. and Brown, M., 1997, Ultrahigh-temperature metamorphism and multi-stage decompressional evolution of sapphirine granulites from the Palni Hill Ranges, Southern India. Journal of Metamorphic Geology, 15, 379-399.

Brown, M. and Rushmer, T., 1997.  Deformation-enhanced Fluid Transport in the Earth's Crust and Mantle. In: Holness, M.B. (ed), Deformation-enhanced Melt Segregation and Metamorphic Fluid Transport. The Mineralogical Society Series: 8. Chapman and Hall, 111-144.

Brown, M. and Raith, M., 1996.  First evidence of ultrahigh-temperature decompression from the granulite province of Southern India. Journal of the Geological Society, London, 153, 819-811.

Brown, M. and Dallmeyer, R.D., 1996. Rapid Variscan exhumation and the role of magma in core complex formation:   Southern Brittany metamorphic belt, France. Journal of Metamorphic Geology, 14, 361-379.

Dallmeyer, R.D., Brown, M., Grocott, J., Taylor, G.K. and Treloar, P.J., 1996. Mesozoic magmatic and tectonic events within the Andean Plate Boundary Zone, 26 -27 30'S, North Chile: Constraints from 40Ar/39Ar mineral ages. Journal of Geology, 104, 19-40.