OCS Aliquots - Atlantic Region

Aliquots are generated from Outer Continental Shelf (OCS) blocks by subdividing each block into 16ths, and this further subdivision allows for more detailed boundary delineation in offshore energy leasing. These polygons are clipped to the Submerged Land Act Boundary and Continental Shelf Boundaries. The aliquots use a letter designation in addition to their parent protraction number and OCS block number (e.g., NK18-02, 6822F). A full OCS block is 4800 x 4800 meters, while an aliquot measures 1200 x 1200 meters. Smaller, clipped aliquots are found along the Federal/State OCS boundary and along UTM zone borders. Only the most recently published paper or PDF versions of the Official Protraction Aliquot Diagram (OPAD) should be used for official or legal purposes.

This data was created in the applicable NAD83 UTM Projection and re-projected to WGS84 Geographic. Because GIS projection and topology functions can change or generalize coordinates, these GIS files are NOT an OFFICIAL record for the exact boundaries. These files are to be used for Cartographic purposes only. This data should not be used to calculate area.