Estimate of gas hydrate resource, northwestern Gulf of Mexico continental slope

Abstract

Estimates of gas hydrate sequestered on the northwestern Gulf of Mexico (NWGOM) continental slope are presented. The volume of gas hydrate reservoir is estimated based on the relationship between geologic setting, water depth and the gas hydrate stability zone. A conceptual model of gas hydrate occurrence defines two types of gas hydrate accumulations in the NW GOM: (1) structurally focused thermogenic and bacterial gas hydrate on the rims of minibasins, and (2) disseminated bacterial methane hydrate that resides within minibasins. Structurally focused gas hydrate is estimated to contain ∼8–11×10 12 m 3 of C 1–C 5 hydrocarbon gas at standard temperature and pressure (STP), representing an important target for future economic exploitation. The estimated volume of bacterial methane hydrate in minibasins is ∼2–3×10 12 m 3 of methane at STP, but appears to be too widely disseminated to represent a viable exploration target. Gas hydrate resource density estimated in this study is at least 15 times less than that calculated from previous gas hydrate resource estimates in the GOM. Furthermore, total gas hydrate resource in the GOM is not likely to significantly exceed gas hydrate resource in the NWGOM estimated in this study.