GOMR Geographic Information System (GIS) Data and Maps

The Mapping & Boundary Branch performs mathematical offshore boundary location computations and prepares Official Protraction Diagrams (OPDs) and Leasing Maps (LMs), and Supplemental Official OCS Block Diagrams (SOBDs) depicting OCS Block information, the Submerged Lands Act Boundary (aka - State Seaward Boundary), Limit of "8(g) Zone", the Continental Shelf Boundary (CSB) which marks the limit of U.S. jurisdiction for offshore mineral development, and corresponding area measurements. For clarification of Acronyms, see Codes and Abbreviations for Map/OPD/Area. The analytical procedures employed and the computer programs utilized to perform various offshore boundary geometric computations are described in OCS Report MMS 99-0006.

  • Gulf of Mexico Geographic Mapping Data
    Geographic mapping data available for free downloading includes cadastral, regulatory, and resource features. Some of the numerous files available include lease, block, and protraction polygons, fairways, pipelines and platforms. Three formats are available for download: ArcInfo, ASCII, and DXF.
  • Gulf of Mexico Lease Information
    Periodically, the Bureau of Ocean Energy Management holds Oil and Gas Lease Sales in the Gulf of Mexico (GOM). Recent sale maps with active leases can be found by viewing the individual sale information from the Lease Sale page.
  • General Purpose Maps
    • GOM Active Leases/Infrastructure (updated August 15, 2014)
      (Visual 1 .pdf) (Visual 1 eps version)

      This map displays active leases, oil and gas structures, pipelines, area boundaries, lease term lines, oil refineries, supply bases, crude oil terminals, and water depth in meters.
    • Western and Central GOM Topographic Features Stipulation Map Package (updated May 2014)

      These maps indicate the areas affected by the Topographic features Stipulation.

For additional information regarding Biological Stipulations questions may be directed to James Sinclair at (504) 736-2789.

Gulf of Mexico Official Protraction Diagram (OPD) & Leasing Maps (LM) Images

Within the Gulf of Mexico, there are two types of maps that depict blocks that could be leased. An older format, known as the Leasing Map, was based on Texas or Louisiana State Plane mapping projections. Leasing Maps were created as oil/gas leasing expanded offshore of Texas and Louisiana.

Eventually the Leasing Maps were projected so far offshore that negative coordinates were required to support the projection. This has created a wide variety of Leasing Maps in projection, shape and overall size, but the blocks remained consistent, and are never larger than the 5760 acres. Because the Leasing Maps reflect so many active leases, they are still being maintained. However, in areas further offshore where Leasing Maps have never been generated, the Official Protraction Diagram (OPD) are used.

A standard OPD is 1 degree in latitude by 2 degrees in longitude (at lower latitudes: 0 - 48 degrees). At higher latitudes (48 - 75 degrees) such as Alaska and northern Washington, OPDs are 3 degrees wide. OPD limits usually approximate the standard 1:250,000 scale U.S. Geological Survey topographic map series. The OPDs are numbered using the United Nations International Map of the World Numbering System. OPD names usually coincide with standard topographic sheet names when diagrams include land areas. OPD sheet names relate to land features, or to hydrographic features contained within the limits of the diagram. Shoreline planimetric detail is shown when it falls within the limits of a diagram. Older OPDs were prepared on mylar with manual cartographic methods and then scanned into Adobe .pdf files. Newer OPDs were prepared electronically and converted to Adobe .pdf files.

LM and OPD Indexes

Gulf of Mexico SOBD Images

A Supplemental Official OCS Block Diagram (SOBD) is prepared for each block intersected by an offshore boundary (Submerged Lands Act Boundary, Limit of "8(g) Zone", National Marine Sanctuaries, etc.). Note that not all OPDs contain such boundaries, therefore not all OPDs have SOBDs associated with them. For the purpose of future Lease Sales, always be sure to use the most recent version.

Image File Formats

The most current approved revision for each Gulf of Mexico Region OPD and SOBD may be viewed and downloaded from the list below. OPDs are offered in Adobe (.pdf) format. OPDs completed after 1996 are also available in Arc/Info Graphics File (.gra) format. SOBDs are available as Adobe (.pdf) files that have been compressed with PKZIP. Free decompression utilities may be downloaded here. Adobe (.pdf) files may be viewed with the free Adobe Acrobat reader.

GIS Files

The various boundaries are also offered as GIS files in both Arc/Info export (.e00) format, and as Arc View shapefiles. Shapefiles can also be viewed with the free Arc Explorer viewer. The shape files have been zipped with Pkzip. Some .e00 export files have been compressed with the UNIX "compress" command. (If they are compressed they will have a .Z extension.) Use the UNIX "uncompress" utility or the free gzip.exe DOS utility.

OPDs can also be purchased by paper copies as maps or in digital formats from the Public Information Office at 1-800-200-GULF.

Note: The precise coordinates of a GIS file can be altered slightly by various GIS functions. For that reason, these GIS files are not an Official Record for offshore boundaries. Only the coordinates shown on Official OPDs, CBDs, and SOBDs constitute an Official Record for offshore coordinate values.

Note: All coordinates for the Gulf of Mexico Region leases and cadastre data are done on the North American Datum of 1927 (NAD 27).

All Current Published Gulf of Mexico (GOM) Region
NAD 27 OPDs and SOBDs

File Name



GOM Official Protraction Diagrams (OPDs)

Adobe (.pdf) format
Updated 01/21/2015

Graphic shows Gulf of Mexico coast and all GOM Region OPDs and Planning Areas.

GOM Supplemental Official OCS Block Diagrams (SOBDs)

Adobe (.pdf) format
Updated 06/28/2007

All published Gulf of Mexico NAD 27 SOBDs.

Planning Areas

Updated 06/20/2002
Updated 09/18/2004

2002-2007 Planning Area Legal Descriptions and Statistics

Official Protraction Diagrams (OPD)

Updated 01/21/2015

All current, published NAD 27 OPDs for the GOM Region in Adobe (.pdf) format have been zipped together in a single file. 


Additional Resources: