USGS
Navigation
Seismic Shot Navigation
Raw DGPS Navigation
The directory rawnav contains the Raw DGPS Navigation that was collected using a USGS differential GPS system (Ashtech). These files were extracted from the SEG-Y seismic trace headers for each unique fix available (~ every 5 sec.). WARNING: These data have not been checked for errors. Use with caution.

Seismic Shot Navigation
The seismic shot navigation is received by the differential GPS system (DGPS), sent directly to the ISIS acquisition system, and recorded in the SEG-Y header of each file. The navigation is later extracted from the header with the shot numbers in a corresponding field. These navigation data have been checked for errors, and are assumed to be correct.

The navigation is stored in ASCII files using eight fields separated by commas. These files are located in the shotnav sub-directory.

  • Field 1: Longitude
  • Field 2: Latitude
  • Field 3: Line Number
  • Field 4: Shot Number
  • Field 5: UTM Zone 18 X
  • Field 6: UTM Zone 18 Y
  • Field 7: Year
  • Field 8: Julian Day:Hour:Minute:Second
 Shotpoint Maps: Full extent of Chirp survey area

Shotpoint Navigation File (ASCII): 95007.txt

Shotpoint SEG-P1 File: Shotpoint Interval: 2000

Cruise Log: MSExcel Format | Text File