NAVIGATION DATA - ARCHIVE OF CHIRP SEISMIC REFLECTION DATA COLLECTED DURING USGS CRUISES 00SCC02 AND 00SCC04, BARATARIA BASIN, LOUISIANA, MAY 12 - 31 AND JUNE 17

RAW SHOTPOINT NAVIGATION

Raw navigation data can be found in the RAWNAV subfolder of the NAV folder located at the top level of each disc. The data are stored by trackline number in flat ASCII text file format with a .txt extension. Each file contains six fields separated by a space. Each of these fields is 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: Julian Day:Hour:Minute:Second (GMT)

WARNING: These data have not been edited. For example, the year is recorded as 2028.

NOTE: The navigation data have not been corrected to reflect the 10 m offset between the shotpoint and the GPS antenna.

EDITED SHOTPOINT NAVIGATION

Edited shotpoint navigation files were extracted from the SEG-Y seismic trace headers using Seismic Unix software. They were edited to remove spurious data values and processed using PROJ.4 (Unix/Linux shareware currently located at http://www.remotesensing.org/proj) to convert latitude and longitude to Zone 15 UTM coordinates.

The edited navigation files can be accessed through the links provided below or from within the EDITNAV subfolder of the NAV folder located at the top level of each disc. Also included are edited 1,000-shot interval files that can be accessed through the links provided below or from within the SHOTNAV subfolder of the NAV folder. These files are all stored by Cruise ID in flat ASCII text file format with a .txt extension. The shotpoint navigation files and 1,000-shot interval files both contain eight fields separated by commas. Each of these fields is 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: Julian Day:Hour:Minute:Second (GMT)

EDITED SHOTPOINT NAVIGATION:
00SCC02 (all lines)
00SCC04 (all lines)

1,000-SHOT INTERVAL NAVIGATION:
00SCC02 (all lines)
00SCC04 (all lines)

NOTE: The navigation data have not been corrected to reflect the 10 m offset between the shotpoint and the GPS antenna.

SEISMIC SHOTPOINT MAPS

The edited shotpoint navigation files and 1,000-shot interval files were used to generate shotpoint maps with ESRI GIS software ArcView 3.2. The maps were then exported to Adobe Illustrator for final editing and conversion to JPEG images. These JPEG images can be found in the MAPS folder located at the top level of each disc. The ESRI ArcView project and shapefiles used to create the maps can be found in the ARC subfolder of the SOFTWARE folder located at the top level of each disc. The project is compatible with ESRI ArcView and ArcGIS software. The shapefiles can also be viewed using ESRI ArcExplorer shareware, which can currently be downloaded from the ESRI website at http://www.esri.com/software/arcexplorer/index.html.

Click on the links below to see the seismic shotpoint maps and access the seismic image files.

00SCC02 FULL SURVEY AREA MAP

00SCC04 FULL SURVEY AREA MAP