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ALPH 98013 Sparker Field Navigation Data and Shotpoint Maps


Click on each of the survey areas for a more detailed map and to view the seismic lines.

navigation map

Click on each of the survey areas for a more detailed map and to view the seismic lines.

Dumpsite Area | Mosaic Area

Shotpoint Navigation Data:

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

Shotpoint Maps:
Full Extent of Sparker Survey
Dumpsite Survey Area
Mosaic Survey Area

Raw Navigation Data:

The raw navigation was collected  using a USGS differential GPS system (Ashtech). These files represent the data that was originally 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. jd254web.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: 254 | 255 | 256 | 257 | 258 | 259 | 260 | 261 | 262 | 263 | 264 | 265
mosaic dumpsite dumpsite mosaic dumpsite dumpsite dumpsite