Navigation Data and Maps

Seismic Trackline Maps

Trackline maps were generated with ESRI GIS software ArcView 3.2 and 8.1, exported to Adobe Illustrator for further editing, and saved in JPEG format. These JPEG images can be found in the MAPS folder. For details about the GIS project included on this disc, refer to the Software page.

Click on the links below to view the trackline maps. Refer to Table 2 for a list of which lines appear on each map.

Full Survey Area Map

Edited Shotpoint Navigation

Navigation files were extracted from the trace headers using Triton Elics Delph Seismic software, and 500-shot interval location files were extracted using Seismic Unix software. These files were edited to remove or correct spurious data points and fix incorrectly recorded dates. The data were then processed using PROJ.4 (Linux/Unix shareware located at http://www.remotesensing.org/proj) to generate Zone 15 UTMs from latitude and longitude and reformat the data for use with ESRI ArcView GIS software. Both sets of coordinates are provided for all lines.

Edited shotpoint navigation files and 500-shot interval location files can be accessed through the links provided below or from within the NAV folder. Edited shotpoint navigation files are located in the EDITNAV folder, and edited 500-shot interval location files are located in the SHOTNAV folder. These files are stored by cruise ID with a .txt extension. Both edited versions contain eight fields separated by commas and defined as follows:

Field 1: UTM Zone 15 X
Field 2: UTM Zone 15 Y
Field 3: Trackline Number
Field 4: Shotpoint Number
Field 5: Longitude (decimal degrees)
Field 6: Latitude (decimal degrees)
Field 7: Year
Field 8: Day of Year:Hour:Minute:Second (GMT)

Edited Shotpoint Navigation:

500-Shot Interval Navigation:

NOTE: The navigation data have not been corrected to reflect any offset between the shotpoint and the GPS antenna.

Raw Shotpoint Navigation

Raw navigation data can be found in the RAWNAV folder. The data are stored by Cruise ID and trackline number with a .txt extension. Each file contains six fields separated by a space and defined as follows:

Field 1: Trackline Number
Field 2: Shotpoint Number
Field 3: Longitude (decimal degrees)
Field 4: Latitude (decimal degrees)
Field 5: Year
Field 6: Day of Year:Hour:Minute:Second (GMT)

WARNING: These data contain errors and have not been edited.

NOTE: The navigation data have not been corrected to reflect any offset between the shotpoint and the GPS antenna.