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[The Tibetan plateau and the high Himalaya]

RESEARCH
My current research includes collisional processes of the Himalaya and gneiss domes of southern Tibet, coexisting pseudotachylite and eclogite-facies shear zones in northern Norway, the tectonic evolution of the ultrahigh-pressure Qinling-Dabie-Sulu orogen in eastern China, and the tectonometamorphic history of subduction complexes in the Ural Mountains of Russia. I am a field geologist with research interests in geochronology, igneous and metamorphic petrology, structural geology and tectonics, and geochemistry.

GRADUATE RESEARCH OPPORTUNITIES (Two application deadlines for admission: November 1 and March 15, annually)
I would like to admit one new graduate student to my research group in Fall 2012. I have NSF-supported graduate research opportunities for field-based study of the petrogenetic affinity of Miocene granites to test the mid-crustal channel flow model in the Himalaya. Projects would also involve laboratory analyses including U-Pb SHRIMP geochronology, ⁴⁰Ar/³⁹Ar thermochronology, or MC-ICP-MS analysis of Hf, Pb, and Nd isotopes. I am looking for students interested in research involving hard-rock petrology, geo/thermochronology, geochemistry, and tectonics on topics related to large-scale orogenic processes. I also encourage students to apply with interests in microstructural deformation processes using EBSD as a tool. Preference will be given to students with previous field and/or lab experience. Please contact me for more information or see the Geosciences Department web site or the Graduate Studies web site for program details and admissions requirements. Women and people from diverse backgrounds are particularly encouraged to apply.

CURRENT STUDENTS

Aileen Chea: Deformation in the Pangong transpressional zone, northern India

Kelsey Kehoe: Phase equilibria and thermobarometry of metabolites from Himalayan gneiss domes

FORMER STUDENTS

Forrest Horton (M.S. 2011): Geochronology and zircon geochemistry of Greater Himalaya leucogranites in Zanskar, NW India (now in a PhD program at UC Santa Barbara)

Pariskeh Hosseini (M.S. 2011): EBSD analysis of partially-eclogitized rocks from the Marun-Keu Complex, Polar Urals, Russia

Deborah Shulman (M.S. 2011): Fluid controlled metamorphism of eclogitic pseudotachylite-bearing shear zones, Flakstadoy, northern Norway (now in a PhD program at the University of Maine)

Will Hassett (M.S. 2010): Geochemical signature of Himalayan gneiss domes: Implications for channel flow

Senior Research Theses

Carla Rosa (B.S. 2011) - Textural analysis of rocks from the Karakoram shear zone, Ladakh, northwestern Indian Himalaya (Now in the MS program at SF State)
Kevin Denton (B.S. 2010) - Paleomagnetic study of the Caetano intra-caldera tuff, Lander County, Nevada (co-advised with Jonathan Glen, U.S.G.S. Menlo Park)
Steve Dutra (B.S. 2010) - Thermobarometry and mineral chemistry of clinopyroxenes in eclogite-facies shear zones in the Lofoten Islands, Norway
Mae Marcaida (B.S. 2010) - Crystallization history of Black Point and Red Cones: Mafic eruptions of the Mono-Inyo volcanic chain, eastern California (co-advised with Margaret Mangan, U.S.G.S. Menlo Park)
Molly Cornell (B.S. 2009) - Characterization of anomalous graphite from the Maksyutov ultrahigh-pressure metamorphic complex, Russia
Christina Polito (B.S. 2006) - Eclogitization of Proterozoic gabbros in the Lofoten Islands, Norway (Now at the Berkeley Geochronology Center)

CURRENT GRANT FUNDING

NSF, 2010-2013, Upgrade of Electron Microscopy Facility to Increase Geoscience Functionality at San Francisco State University
NSF, 2009-2014, Petrogenetic affinity of Miocene granites to test the mid-crustal channel flow model in the Himalaya

PREVIOUS GRANT FUNDING

NSF, 2008-2011, Acquisition of a FE-SEM to enhance research and student training in Biology, Chemistry, Geosciences, Physics, and Engineering at San Francisco State University
NSF, 2001-2005, Subduction and exhumation of ultrahigh-pressure rocks: Field and drilling studies in eastern China
NSF-AAAS, 2003-2004, Collaborative research on the petrotectonic evolution of the ultrahigh-pressure Tso Morari Crystallines, western Himalaya, India

LABORATORY FACILITIES IN GEOSCIENCES

Zeiss Ultra 55 Field emission scanning electron microscope with BSE, STEM detector, Oxford INCA EDS and EBSD (using Channel 5 software), and Gatan MiniCL. We use the SEM in conjunction with an XEI Evactron plasma cleaner and ibss Gentle Asher to maintain a clean sample chamber. Sample prepartion equipment includes a Gatan Model 682 PECS + RIBE that is a coater/ion beam etcher, a Cressington 208HR sputter coater, a Cressington 208C carbon coater equipped with sample holders specifically for geological thin sections, and a critical point dryer (web site in development - for inquiries about training/use of our SEM, please contact the facility manager, Dr. Clive Hayzelden, at image "AT" sfsu.edu).

Mineral separation/sample preparation lab - Rock saws, thin sectioning equipment, grinder/polisher, vibratory polisher, jaw crusher, disk mill, shatterbox, slope Frantz magnetic separator, ovens, lap wheels, seives, rock storage

Bruker D8 ADVANCE powder x-ray diffractometer

Various spectrometers, gas and liquid chromatographs, radiochemistry facilities and equipment, centrifuges, lasers, etc. (in the Department of Chemistry and Biochemistry)

Scanning laser confocal microscope, fluorescence and epi-fluorescence microscopes, and a dissecting scope (in the Cell and Molecular Imaging Center, Department of Biology)

Gas chromatograph stable isotope analyzer, elemental analyzer, etc. (at the Romberg Tiburon Center for Environmental Studies)

Machine and glass shops, and an electronics repair facility

COURSES TAUGHT
Currently offered
Geochemistry * (Spring semesters - even years)
Mineralogy and Petrology I * (Spring semesters)
Mineralogy and Petrology II * (Fall semesters)
Volcanology * (Fall semesters)

Offered in the past
Science Partners in K-12 Education
Tectonic Geomorphology *
The Violent Earth
Earthquakes and the San Andreas fault *
Geology of the National Parks
California Rocks!
* External users can contact me via e-mail for access to course materials on iLearn

PUBLICATIONS

The Himalaya and southern Tibet

Klemperer, S.L., Kennedy, B.M., Sastry, S.R., Makovsky, Y., Harinarayana, T., and Leech, M.L., in review, Mantle helium signature implies the Karakoram fault is an active plate boundary, Nature Geoscience.
Leech, M.L., Klemperer, S.L., and Mooney, W.D., 2010, Proceedings for the 25th Himalaya-Karakoram-Tibet Workshop, San Francisco, California, U.S.A.: U.S. Geological Survey, Open-File Report 2010-1099, 242 p.
Leech, M.L., 2009, Reply to comment by M.P. Searle and R.J. Phillips (2009) and R.R. Parrish (2009) on: "Does the Karakoram fault interrupt mid-crustal channel flow in the western Himalaya?", Earth and Planetary Science Letters (2009), doi:10.1016/j.epsl.2009.05.039. This pdf also includes the two comments.
Leech, M.L., 2008, Does the Karakoram fault interrupt mid-crustal channel flow in the western Himalaya?, Earth and Planetary Sciences, 276, 314-322.
Leech, M.L., Singh, S., and Jain, A.K., 2008, Continuous metamorphic zircon growth and interpretation of U-Pb SHRIMP dating: An example from the western Himalaya: In, Metamorphic conditions along convergent plate junctions: Mineralogy, petrology, geochemistry, and tectonics (W.G. Ernst and D. Rumble III, eds.), Geological Society of America International Book Series, 10, 433-448.
Leech, M.L., Singh, S., Jain, A.K., 2007, Continuous metamorphic zircon growth and interpretation of U-Pb SHRIMP dating: An example from the western Himalaya, International Geology Review, 49, 313-328.
Leech, M.L., Singh, S., Jain, A.K., and Klemperer, S.L., and Manickavasagam, R.M., 2006, Reply to comment by P.J. O'Brien on: "The onset of India-Asia continental collision: Early, steep subduction required by the timing of UHP metamorphism in the western Himalaya", Earth and Planetary Science Letters, 245, 817-820.
Leech, M.L., Singh, S., Jain, A.K., and Klemperer, S.L., and Manickavasagam, R.M., 2005, The onset of India-Asia continental collision: Early, steep subduction required by the timing of UHP metamorphism in the western Himalaya, Earth and Planetary Science Letters, 234, 83-97.

Eastern China
Leech, M.L. and Webb, L.E., in review, Is the HP-UHP Dabie-Sulu orogen a piercing point for offset on the Tan-Lu fault? Journal of Asian Earth Sciences.
Yang, T.N., Peng, Y., Leech, M.L., and Lin, H.Y., 2011, Fold patterns indicating Triassic constrictional deformation on the Liaodong peninsula, eastern China, and tectonic implications, Journal of Asian Earth Sciences, 40,72-83, doi:10.1016/j.jseaes.2010.08.017.
Leech, M.L., Webb, L.E., and Yang, T., 2006, Diachronous histories for the Dabie-Sulu orogen from high-temperature geochronology, Geological Society of America Special Paper 403, 1-22.
Webb, L.E., Leech, M.L., and Yang, T., 2006, ⁴⁰Ar/³⁹Ar thermochronology of the Sulu terrane: Late Triassic exhumation of high and ultrahigh-pressure rocks and other implications for Mesozoic tectonics in East Asia. Geological Society of America Special Paper 403, 77-92.
Yang, T., Xu, Z., and Leech, M.L., 2004, Mass balance during retrogression of eclogite-facies minerals in the Rongcheng eclogite, eastern Sulu UHPM terrane, China, American Mineralogist, 89, 1525-1532.

The Ural Mountains, Russia
Beane, R.J. and Leech, M.L., 2007, The Maksyutov Complex: The first UHP terrane 40 years later, in Cloos, M., Carlson, W.D., Gilbert, M.C., Liou, J.G., and Sorensen, S.S., eds., Convergent Margin Terranes and Associated Regions: A Tribute to W.G. Ernst: Geological Society of America Special Paper 419, p.153-169, doi: 10.1130/2006.2419(08).
Leech, M.L. and Willingshofer, E., 2004, Thermal modeling of an ultrahigh-pressure complex in the south Urals, Earth and Planetary Science Letters, 226, 85-99.
Bostick, B., Jones, R.E., Chen, C., Ernst, W.G., Leech, M.L., and Beane, R.J., 2003, Low-temperature microdiamond aggregates in the Maksyutov metamorphic complex, south Ural Mountains, Russia, American Mineralogist, 88, 1709-1717.
Leech, M.L., 2001, Arrested orogenic development: eclogitization, delamination, and tectonic collapse, Earth and Planetary Science Letters, 185, p. 149-159.
Leech, M.L. and Ernst, W. G., 2000, Petrotectonic evolution of the high- to ultrahigh-pressure Maksyutov Complex, Karayanova area, south Ural Mountains: Structural and oxygen isotope constraints, Lithos, 52, p. 235-252.
Leech, M.L. and Stockli, D.F., 2000, The late exhumation history of the ultrahigh-pressure Maksyutov Complex, south Ural Mountains, from new apatite fission track data, Tectonics, 19, p. 153-167.
Leech, M.L., 1999, Petrotectonic evolution of the Maksyutov Complex, south Ural Mountains, Russia, Ph.D. dissertation, Stanford University, 117 p.
Ernst, W.G., Mosenfelder, J.L., Leech, M.L., and Liu, J., 1998. H₂O recycling during continental collision: phase-equilibrium and kinetic constraints. In When Continents Collide, eds., B.R. Hacker and J.G. Liou, Kluwer Academic, Netherlands, 275-295.
Leech, M.L. and Ernst, W.G., 1998. Graphite pseudomorphs after diamond? A carbon isotope and spectroscopic study of graphite cuboids from the Maksyutov Complex, south Ural Mountains, Russia. Geochimica et Cosmochimica Acta, 62, p. 2143-2154.
Beane R.J., Liou J.G., Coleman R.G., and Leech M.L., 1995. Mineral assemblages and P-T path for high- to ultrahigh-pressure metamorphism in the Maksyutov Complex, Ural Mountains, Russia. Island Arc, 4, p. 254-266.
Lennykh V.I., Valizer P.M., Beane R.J., Leech M.L., and Ernst W.G, 1995. Petrotectonic evolution of the Maksyutov Complex, south Urals, Russia: Implications for ultrahigh-pressure metamorphism. International Geology Review, 37, p. 584-600.

Norway
Shulman, D.J. and Leech, M.L., in review, Fluid-controlled metamorphism of eclogitic pseudotachylite-bearing shear zones, FlakstadØy, northern Norway, Journal of Metamorphic Geology.

Other publications
Leech, M.L., Howell, D.G., and Egger, A.E., 2004, A guided inquiry approach to learning the geology of the U.S., Journal of Geoscience Education, 52, 368-373.

CLASSROOM EXERCISES

Geologic provinces of the U.S. (with David Howell at the U.S. Geological Survey)

** Updated 2 February 2012 **

Department of Geosciences
San Francisco State University

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