NAVIGATION DATA - ARCHIVE OF BOOMER SEISMIC REFLECTION DATA COLLECTED DURING USGS CRUISES 01SCC01 AND 01SCC02, TIMBALIER BAY AND OFFSHORE OF EAST TIMBALIER ISLAND, LOUISIANA, JUNE

SEISMIC TRACKLINE MAPS

The edited shotpoint navigation files and 500-shot interval files were used to generate trackline maps with ESRI GIS software ArcView 3.2 and 8.1. The maps were then exported to Adobe Illustrator for further editing and saved for the web in JPEG format. These JPEG images can be found in the MAPS folder located at the top level of this disc. The ESRI ArcView map documents and shapefiles used to create the maps can be found in the ARC subfolder of the SOFTWARE folder located at the top level of this disc. The map documents are compatible with ESRI ArcGIS 8.x 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 trackline maps and access the seismic image files.

FULL SURVEY AREA MAP

EDITED SHOTPOINT NAVIGATION

Shotpoint navigation files were extracted from the SEG-Y seismic trace headers using Seismic Unix software and edited to remove spurious data values. They were then processed using PROJ.4 (Unix/Linux shareware currently located at http://www.remotesensing.org/proj) to convert UTMs to latitude and longitude for lines 01b001 - 01b080 and latitude and longitude to UTMs for lines 01b082 - 01b093. Both Zone 15 UTMs and latitude and longitude are provided for all lines.

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 this disc. Also included are edited 500-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. 01SCC02 navigation is divided into part a (lines 01b047 - 01b080, collected in UTMs) and part b (lines 01b082 - 01b093, collected in latitude and longitude). The shotpoint navigation files and 500-shot interval files both contain eight fields separated by commas. Each of these fields is defined as follows:

Lines 01b001 - 01b080

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

Lines 01b082 - 01b093

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:

500-SHOT INTERVAL NAVIGATION:

NOTE: The navigation data have not been corrected to reflect the 20-m offset between the shotpoint and the GPS antenna.

RAW SHOTPOINT NAVIGATION

Raw navigation data can be found in the RAWNAV subfolder of the NAV folder located at the top level of this 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. These fields are defined as follows:

Lines 01b001 - 01b080

Field 1: Trackline Number

Field 2: Shotpoint Number

Field 3: UTM Zone 15 X

Field 4: UTM Zone 15 Y

Field 5: Year

Field 6: Julian Day:Hour:Minute:Second (GMT)

Lines 01b082 - 01b093

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.

NOTE: The navigation data have not been corrected to reflect the 20-m offset between the shotpoint and the GPS antenna.