CAREER: Petrogenetic Affinity of Miocene Granites to Test the Mid-crustal Channel Flow Model in the Himalaya

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The main goal of the research project is to test the channel flow model that predicts granite melts of Indian crust thrust beneath the Tibetan plateau are gravitationally-driven south to the topographic erosional front of the Himalaya. These granites are exposed in the Greater Himalaya Sequence in the topographic front of the Himalaya, in granite gneiss domes in the Tethyan Himalaya Sequence further north, and may be exposed along the Karakoram fault in the southern Tibetan plateau. The channel flow model will be tested using a combination of field observations, U-Pb and 40Ar/39Ar geochronology, and Nd and Pb isotope geochemistry to determine the sources of these Miocene granites in the western Himalaya (India) and the eastern Himalaya (southern Tibet). Results of this research will support or argue against the channel flow model in the Himalaya; identify the source of Miocene granites in the Karakoram, Himalaya, and southern Tibet; establish the northern reach of underthrust Indian crust beneath the Tibetan plateau; and may establish whether the Karakoram fault is a crustal-scale structure as well as constrain the timing of slip on the fault. Geodynamic models developed for the Himalaya are commonly exported to other collisional orogens worldwide: most recently, the channel flow model has been applied to the Appalachians, the Canadian Cordillera, and the Hellenides. The channel flow model explicitly links climate-driven surface processes with deep crustal processes in the context of topographic gradients set up by continental collision and as a result has pushed geological research in new directions connecting tectonic processes to regional and global climate change.The education plan for this project creates a new course at San Francisco State University, "Science Education Partners in Geosciences", that will partner undergraduate and graduate students in Geosciences with grade 3 to 6 teachers to co-develop and co-teach lessons in San Francisco Unified School District classrooms. In California, an area of great earthquake hazard, and a state with major land use and water resource challenges even prior to climate change, there is a particular need for scientifically literate citizens. The only year in which California science standards require Earth Science as the focus of K-12 science instruction is the 6th grade; Earth Science comprises approximately one-third of required science instruction at the elementary level (through grade 5), and an even smaller component in high school, making intervention at grades 3 through 6 the most promising opportunity to enhance K-12 earth science literacy in California public schools. The most important broader impact of this partnership program will be the creation of a cadre of graduates with experience in classroom teaching and outreach, and a group of elementary school teachers empowered to teach engaging earth science lessons.This CAREER award is supported by Tectonics, Petrology and Geochemistry, and Education and Human Resources programs in the Division of Earth Sciences.