Single-beam bathymetry data along with DGPS navigation data was collected as part of the U.S. Geological Survey cruise J-3-99-SF. The cruise was conducted in Grizzly Bay and San Francisco Bay, California from November 8 to November 18, 1999. The chief scientist was John Chin from the USGS Coastal and Marine Geology office in Menlo Park, CA. The purpose of this cruise was to survey Grizzly Bay and adjacent areas for seasonal changes in bottom morphology and sediment texture. The geophysical source was a 200 kilohertz (kHz) system. These data are reformatted from space-delimited ASCII text files located in the Coastal and Marine Geology Program (CMGP) InfoBank field activity catalog at http://walrus.wr.usgs.gov/infobank/j/j399sf/html/j-3-99-sf.meta.html into MGD77T format provided by the NOAA's National Geophysical Data Center(NGDC). The MGD77T format includes a header (documentation) file (.h77t) and a data file (.m77t). More information regarding this format can be found in the publication listed in the Cross_reference section of this metadata file.