Type File Geodatabase Feature Class
Aliquots and other cadastre information the BOEM produces are generated in accordance with 30 Code of Federal Regulations (CFR) Part 556.8 Subpart A, (formerly Part 256.8 Subpart A (2010)) to support Federal land ownership and mineral resource management.
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.
These data were created in the applicable NAD83 UTM or NAD27 UTM/SPCS Projection and re-projected to GCS WGS84 (EPSG 4326) for management in BOEM's enterprise GIS. However, this service in this collection has been published in WGS 1984 Web Mercator Auxiliary Sphere (EPSG 3857). Because GIS projection and topology functions can change or generalize coordinates, these data are NOT an OFFICIAL record for the exact boundaries. These data are to be used for Cartographic purposes only and should not be used to calculate area.
Bureau of Ocean Energy Management (BOEM), Office of Strategic Resources (OSR), Geospatial Services Division (GSD)
https://www.usa.gov/publicdomain/label/1.0/
| West | -159.929761 | East | -63.905589 |
| North | 48.505897 | South | 16.953032 |
| Maximum (zoomed in) | 1:5,000 |
| Minimum (zoomed out) | 1:150,000,000 |
Bureau of Ocean Energy Management (BOEM), Office of Strategic Resources (OSR), Geospatial Services Division (GSD)
National Dataset covering Atlantic Coast, Pacific West Coast, Gulf of Mexico (offshore Texas and Louisiana only), a portion of Hawaii, and a portion of Puerto Rico and U.S. Virgin Islands.
https://www.usa.gov/publicdomain/label/1.0/
This national dataset was created using data from both TIMS and BDS. The data generated from TIMS was imported from an oracle database into a geodatabase using the TIMS to BDS ETL. The data is stored in the applicable NAD83 (Atlantic, Alaska, Gulf of Mexico and Pacific Coast, Puerto Rico, and U.S. Virgin Islands) and WGS84 (Hawaii and Pacific Territories) and appended to the WGS84 Geographic national geodatabase to display as the OCS Aliquot 16ths Polygons – 3rd Division national dataset. The BDS Frontier Tool was used to generate the Protraction, Block and Aliquots for the Atlantic, Pacific, Territories and Gulf of Mexico areas only. The BDS OMC Dataset Creator was used to generate the National dataset and clip the Protractions, Block and Aliquots to the Submerged Land Act (SLA) Boundary and the Continental Shelf Boundary (CSB). This November 10, 2023, dataset is to be used as official cadastre data and is available for download.
OCS Aliquot 16 Polygons – 3rd Division
BOEM
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
The identifier of the subdivision of an Official Protraction Diagram or Leasing Map that the block corner point falls within.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
The identifier of the Official Protraction Diagram or Leasing Map that the aliquot falls within.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
The name of the Official Protraction Diagram or Leasing Map that the aliquot falls within.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
The total surface area within an OCS aliquot. This includes all state, unencumbered federal and/or encumbered federal portions, such as deferred, disputed, Section 8(g), and/or withdrawn parcels. It is measured in acres or hectares as appropriate. The total area in an aliquot does not exceed 355.83 acres or 144 hectares.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
An explanation or description associated with individual aliquot records..
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
The indicator used to identify the appropriate unit of areal measurement for the OPD or Leasing Map. All Leasing Maps in the State Plane Coordinate System have areas measured in acres. All OPDs in the UTM coordinate system have areas measured in hectares.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
The month, day, and year of the OCS Block that the boundary line resides within.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
The day, month, year the block is associated to the Official Protraction Diagram or Leasing Map it falls within and is uploaded to the database.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
Concatenated block and aliquot label used for maps.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
Uppercase aliquot label used for maps.
BOEM Boundary Delineation System
Field in a feature class does not originate with any metadata authority.
Feature geometry.
Esri
Coordinates defining the features.
Length of feature in internal units.
Esri
Positive real numbers that are automatically generated.
Area of feature in internal units squared.
Esri
Positive real numbers that are automatically generated.