Lateral Variations in Mantle Velocities
{'Code': '06030204', 'Directorate': {'Abbreviation': 'GEO', 'LongName': 'Directorate For Geosciences'}, 'Division': {'Abbreviation': 'EAR', 'LongName': 'Division Of Earth Sciences'}}
{'SignBlockName': 'James H. Whitcomb', 'PO_EMAI': None, 'PO_PHON': None}
The seismological study of the three-dimensional structure of              the earth's interior is a very active area of current research,                 with a variety of different methods and data types being applied                to the problem.  In a previous grant a new and effective approach               to this problem was developed which used short-period body wave                 travel time data from ISC bulletins to estimate the intercept time              tau as a function of slowness in a tectonically regionalized                    Earth, and this led to meaningful results concerning the lateral                heterogeneity of P velocities in the shallow mantle.  Taking                    advantage of information already acquired about the shallow                     heterogeneity, a tomographic approach will be used to estimate                  deeper and more general lateral heterogeneity in the mantle.                    Three basic tasks are proposed.  The first will involve the                     refinement of the regionalized tau studies of P and S velocities                in the shallow mantle and a number of tests to check the                        reliability of these estimates.  The second will concentrate on                 subduction zones and will use the existence of earthquakes at                   various depths to estimate incremental velocities within these                  zones.  The third and major task will be a tomographic imaging of               the entire mantle using ISC travel time data.
{'FirstName': 'Lane', 'LastName': 'Johnson', 'PI_MID_INIT': 'R', 'PI_SUFX_NAME': None, 'PI_FULL_NAME': 'Lane R Johnson', 'EmailAddress': 'lane@seismo.berkeley.edu', 'NSF_ID': '000382787', 'StartDate': '03/01/1988', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'University of California-Berkeley', 'CityName': 'BERKELEY', 'ZipCode': '947101749', 'PhoneNumber': '5106433891', 'StreetAddress': '1608 4TH ST STE 201', 'StreetAddress2': None, 'CountryName': 'United States', 'StateName': 'California', 'StateCode': 'CA', 'CONGRESSDISTRICT': '12', 'CONGRESS_DISTRICT_ORG': 'CA12', 'ORG_UEI_NUM': 'GS3YEVSS12N6', 'ORG_LGL_BUS_NAME': 'REGENTS OF THE UNIVERSITY OF CALIFORNIA, THE', 'ORG_PRNT_UEI_NUM': None}
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{'Code': '1574', 'Text': 'Geophysics'}
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1987&All=true', 'xml': '8720879.xml'}