BOEM Releases National Assessment of Undiscovered Oil and Gas Resources on the OCS

Release Date

As part of its mission to manage development of U.S. Outer Continental Shelf (OCS) energy and mineral resources, BOEM today released the 2021 National Assessment, an estimate of the undiscovered, technically and economically recoverable oil and natural gas resources outside of known oil and gas fields.

Published every five years, the National Assessment represents BOEM’s current understanding of the distribution of undiscovered oil and gas resources on the OCS. Any changes from previous assessments reflect additional data and information acquired up to data cutoff of January 1, 2019. Recent updates to the assessment methodology also account for some changes to resource estimates.

BOEM estimates mean Undiscovered Technically Recoverable Resources (UTRR) of 68.79 billion barrels of oil and 229.03 trillion cubic feet of gas in the OCS. The 2016 assessment estimated a mean UTRR of 90.55 billion barrels of oil and a mean UTRR of 327.58 trillion cubic feet of natural gas.

Of BOEM’s four regions, the 2021 estimates of UTRR for the Gulf of Mexico showed the most change from 2016, due in part to the refinement of field size distributions and the estimated number of prospects for some mature geologic plays, particularly on the shallow water shelf.

The findings are derived from analyzing each geologic play across the OCS and assigning a probability for the existence of undiscovered oil and gas resources for individual plays. Play results are then aggregated up to regional results and eventually, a total OCS estimate. The 2021 assessment represents a comprehensive appraisal through the rigorous analysis of the best scientific data and information available as of January 1, 2019, and builds upon previous OCS resource assessments.