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Navigation

USGS Cruise MGNM 99023 Boomer Survey
Field Navigation Data & Shotpoint Maps

Click on one of the survey areas for a more detailed map and to access the seismic image files.

navigation map

Nearshore Area | Hudson Shelf Valley Area



Shotpoint Navigation Data:

The navigation is stored in ASCII files using eight fields separated by commas.
  • Field 1: Longitude
  • Field 2: Latitude
  • Field 3: Line Number
  • Field 4: Shot Number
  • Field 5: UTM Zone 18 Easting
  • Field 6: UTM Zone 18 Northing
  • Field 7: Year
  • Field 8: Julian Day:Hr:Min:Sec
Shotpoint Navigation Files (ASCII):

Nearshore Area | Hudson Shelf Valley Area

Shotpoint Maps:

Nearshore Area | Hudson Shelf Valley Area

Raw Navigation Data:

The raw navigation was collected using a differential GPS system (Ashtech). These files represent the raw data recorded on floppy disk aboard ship. The data are in NEMA format. WARNING: These data have not been checked for errors. Use with caution.

To aid viewing of the original raw navigation data, each data entry was reformatted (removing the NEMA codes) by filtering the raw data files through a UNIX awk script.. Every navigation fix from the original data has been preserved however.

The navigation is stored in ASCII files using six fields separated by tabs, with each file representing a separate julian day (i.e. jd208web.txt). Navigation fixes are at 10 second intervals. The start and end of each line is marked within each reformatted navigation file.
Download Files (click on the Julian Day):
Julian Day: 208 | 209 | 210 | 211 | 212




valley nearshore valley nearshore