Abstract:
This data set contains Official Protraction Diagrams (OPDs) in Adobe PDF format. At lower latitudes (0-48 degrees) OPDs are 1 degree in latitude by 2 degrees in longitude. At higher latitudes (48-75 degrees) OPDs are 3 degrees wide. OPDs are further subdivided into blocks that are 4800 x 4800 meters on a UTM grid but this file does not include those blocks - only the OPD outline). Where the OPD hits the UTM zone boundary, that zone boundary will be a geodesic line - which will appear slightly curved on the UTM grid. OPDs are numbered using the United Nations International Map of the World Numbering System, and are generally named for land or hydrographic features contained within the limits of the diagram. Further information on the historic development of OPDs can be found in OCS Report MMS 99-0006: Boundary Development on the Outer Continental Shelf: http://www.boem.gov/BOEM-Newsroom/Library/Publications/1999/99-0006-pdf.aspx. Also see the metadata for each of the individual GIS files used to create these OPDs. The Official Protraction Diagrams (OPDs) and Supplemental Official Block Diagrams (SOBDs), serve as the legal definition for BOEM offshore boundary coordinates and area descriptions.
Supplemental_Information:
The BOEM is making its existing cadastre data available at http://www.boem.gov/Oil-and-Gas-Energy-Program/Mapping-and-Data/Index.aspx. These data include Official Protraction Diagrams (OPDs), and Supplemental Official OCS Block Diagrams (SOBDs) in pdf format, and digital spatial data in ArcGIS shapefile format.