Carlos Alonso, Larry Boudreau, Kellie Cross, Shane Stradley, BOEM
The Gulf of Mexico (GOM) energy basin is comprised very large accumulations of porous sedimentary rocks with proven hydrocarbon trapping capability. Over 23,000 depleted oil and gas reservoirs have been identified in the GOM Outer Continental Shelf (OCS). The Bureau of Ocean Energy Management’s (BOEM) resource stewardship includes a wealth of 3D seismic and downhole geologic, geophysical, engineering, and production data that provides a natural through line to reimagine long-term planning for oil and gas developments that includes consideration of CO₂ geologic sequestration (GS). Although BOEM recognizes CO₂ GS in saline aquifers and Enhanced Oil Recovery (EOR) that segues to GS as viable approaches, we emphasize that depleted reservoirs are verified “containers” that offer proven trapping capabilities and available pressure margins.
BOEM developed a GIS-based approach to identify suitable depleted reservoirs that could serve as GS candidates. The first-order considerations to filter tiers of potential geologic systems would include: 1) distance from shore; 2) water depth; 3) trap structural style; 4) reservoir depth; 5) reservoir depletion volume; 6) porosity, and 7) spatial distribution across the inshore OCS. BOEM has identified 9 fields/21 reservoirs as Tier 1 Depleted Reservoirs for GS in the GOM. BOEM is investigating additional derived or calculated reservoir parameters for filtering of specific desired characteristics for GS projects. BOEM’s ultimate goal is to make available the tools that allow operators to begin with an end in mind that considers CO₂ for GS goals before leases are terminated and valuable infrastructure removed.