Characterization and Detection of Mantle Discontinuities
{'Code': '06030204', 'Directorate': {'Abbreviation': 'GEO', 'LongName': 'Directorate For Geosciences'}, 'Division': {'Abbreviation': 'EAR', 'LongName': 'Division Of Earth Sciences'}}
{'SignBlockName': 'Patricia Brooking', 'PO_EMAI': 'pbrookin@nsf.gov', 'PO_PHON': '7032924728'}
A major unresolved question in global seismology, the                   important implications for Earth structure and dynamics, remains                the detection and accurate characterization of discontinuities                  of the transition zone, the jumps on elastic parameters are                     known approximately, as well as their average locations, while                  for others we have merely indirect evidence of their existence.                         We propose to investigate the structure of the transition               zone, with particular emphasis on the characterization of                       discountinuities.  To achieve this, we have developed a procedure               for inferring the properties of a discontinuity from a sparse                   network of three commponent stations.  This uses a hybrid                       reflectivity - WKBJ approach to the systematic generation of all                phases of non-negligible amplitude that interact with a parti-                  cular boundary, combined with optimal estimates of body wave                    vector displacement to constrain the observed ray parameter.  By                incorporating a variety of reflected and converted phases for                   many events, at different depths and with a range of ray para-                  meters, we can separate the effects of jumps in wave speeds and                 density, while by using broad band data we can also estimate                    thickness.
{'FirstName': 'Paul', 'LastName': 'Silver', 'PI_MID_INIT': 'G', 'PI_SUFX_NAME': None, 'PI_FULL_NAME': 'Paul G Silver', 'EmailAddress': 'silver@dtm.ciw.edu', 'NSF_ID': '000445580', 'StartDate': '09/15/1987', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'Carnegie Institution of Washington', 'CityName': 'WASHINGTON', 'ZipCode': '200151305', 'PhoneNumber': '2023876400', 'StreetAddress': '5241 BROAD BRANCH RD NW', 'StreetAddress2': None, 'CountryName': 'United States', 'StateName': 'District of Columbia', 'StateCode': 'DC', 'CONGRESSDISTRICT': '00', 'CONGRESS_DISTRICT_ORG': 'DC00', 'ORG_UEI_NUM': 'ZQ12LY4L5H39', 'ORG_LGL_BUS_NAME': 'CARNEGIE INSTITUTION OF WASHINGTON', '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': '1574', 'Text': 'Geophysics'}
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1987&All=true', 'xml': '8708195.xml'}