Little investigation of the continental slope and rise with respect to their oil potential has been made, mainly because their depths are much greater than presently is practicable for oil and gas exploitation, and partly because national jurisdictions have not been established. The continental slope overlies the general seaward limit of continental-crustal rocks, but these rocks are covered with sedimentary strata that have prograded beyond the original position of the continental slope. The sedimentary strata are chiefly Cenozoic and Mesozoic in age; they have a seaward dip, and they include few sandstone layers suitable for accumulation of oil and gas.

Sediments of the continental rise lap against the continental slope and contain many good acoustic reflecting horizons that are believed to be the surfaces of sand bodies deposited by turbidity currents. The strata between the reflectors are silt and clay that were deposited slowly from suspension; many of them have slumped from the continental slope where they were deposited originally beneath oxygen-poor water that permitted the accumulation of relatively high concentrations of organic matter. The interbedded position of organic-rich silt and clay (source beds) and of turbidite sand bodies (reservoir beds), which pinchout and are structurally deformed near the heads of the continental rises of the world, may constitute a geologic environment in which large oil and gas accumulations ave developed. Exploratory drilling is needed before possible exploitation can be considered.

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