Isotopic and Petrologic Investigations Into the Development of a Young (~100 Ma) Sialic Crustal Section-Southern Sierra Nevada, California
{'Code': '06030103', 'Directorate': {'Abbreviation': 'GEO', 'LongName': 'Directorate For Geosciences'}, 'Division': {'Abbreviation': 'EAR', 'LongName': 'Division Of Earth Sciences'}}
{'SignBlockName': 'Jane M. Ernst', 'PO_EMAI': None, 'PO_PHON': None}
The southern Sierra Nevada offers an oblique section                    through young batholith-generated sialic crust from surface                     (volcanic) levels to deep (granulitic) levels.  Regional                        mapping and Pb/U zircon geochronology reveal structural                         continuity through this crustal section for igneous-metamorphic                 assemblages of  100 Ma, making it one of the youngest sialic                    crustal sections in the world.  Compositional and structural                    patterns observed  in this section in conjunction with                          geophysical data pose important problems on sialic crustal                      genesis and the nature of lower continental crust. NSF funds                    are sought for the PI and two graduate students for isotopic,                   petrologic and field studies into such problems.  The funds                     sought constitute the main basis of support and scientific                      utilization of a recently acquired (NSF-Caltech cost-share)                     multicollector thermal ionization mass spectrometer.  Some                      specific aims of the proposed research include (1) isotopic,                    geochemical and petrographic characterization of an apparent                    major mantle-derived igneous suite that was added to the crust                  at  100 Ma, and consideration of its role in the formation of a                 granulitic lower crust; (2) study of crustal melting phenomena                  imposed by this mantle igneous suite on a variety of pre-                       existing crustal materials that are known to characterize much                  of the prebatholithic framework based on regional map relations;                (3) application of appropriate thermobarometers to deep-level                   exposures as a test for a gross crustal structure model and for                 constraints on the physical conditions of peak metamorphism and                 crustal melting; and (4) construction of mixing models between                  the young mantle component and pre-existing crustal materials                   and the application of these models to large-scale problems of                  batholith petrogenesis and emplacement.  The mixing phenomena                   will be studied mainly by Nd-Sr isotopic techniques in well-                    understood deep-level domains which exhibit melting and mixing                  relations with the aid of selected oxygen isotope and trace                     element data.  Large-scale goals of this research are to model                  the major components and material transport patterns that                       contributed to the production of the southern Sierra sialic                     crustal column.  This research will also shed new light on                      auriferous ore generation that was widespread along the western                 wall of the Sierra Nevada batholith.
{'FirstName': 'Jason', 'LastName': 'Saleeby', 'PI_MID_INIT': 'B', 'PI_SUFX_NAME': None, 'PI_FULL_NAME': 'Jason B Saleeby', 'EmailAddress': 'jason@gps.caltech.edu', 'NSF_ID': '000445586', 'StartDate': '07/01/1987', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'California Institute of Technology', 'CityName': 'PASADENA', 'ZipCode': '911250001', 'PhoneNumber': '6263956219', 'StreetAddress': '1200 E CALIFORNIA BLVD', 'StreetAddress2': None, 'CountryName': 'United States', 'StateName': 'California', 'StateCode': 'CA', 'CONGRESSDISTRICT': '28', 'CONGRESS_DISTRICT_ORG': 'CA28', 'ORG_UEI_NUM': 'U2JMKHNS5TG4', 'ORG_LGL_BUS_NAME': 'CALIFORNIA INSTITUTE OF TECHNOLOGY', 'ORG_PRNT_UEI_NUM': None}
{'Name': None, 'CityName': None, 'StateCode': None, 'ZipCode': None, 'StreetAddress': None, 'CountryCode': None, 'CountryName': None, 'StateName': None, 'CountryFlag': None, 'CONGRESSDISTRICT': None, 'CONGRESS_DISTRICT_PERF': '""'}
{'Code': '1572', 'Text': 'Tectonics'}
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1987&All=true', 'xml': '8708266.xml'}