EarthWorks Geospatial Catalog

Atlantic NAD 83 OCS Blocks

This data set contains OCS block outlines in ArcGIS shape file format for the BOEMRE Atlantic Region. OCS blocks are used to define small geographic areas within an Official Protraction Diagram (OPD) for leasing and administrative purposes. These blocks have been clipped along the Submerged Lands Act (SLA) boundary and along the Continental Shelf Boundaries. Additional details are available from: Because GIS projection and topology functions can change or generalize coordinates, and because shapefiles cannot represent true arcs, these GIS files are considered to be approximate and are NOT an OFFICIAL record for the exact block coordinates or areas. The Official Protraction Diagrams (OPDs) and Supplemental Official Block Diagrams (SOBDs) serve as the legal definition for BOEMRE offshore boundary coordinates and area descriptions.
Bureau of Ocean Energy Management, Regulation and Enforcement, Mapping and Boundary Branch
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