Abstract In recognizing that we are at a very early stage of exploring the geology and hydro-carbon potential of the Earth’s deeper water areas, an attempt is made to generalize the geological conditions that exist on the continental slopes, the rises and the remainder of the oceanic provinces. An attempt is also made to relate the postulated geology of these provinces to the conditions of structure and stratigraphy required to yield commercially extractable hydrocarbons in what must be a high cost operation. It is fully appreciated that there is much that we do not know about the geology of the more deeply submerged regions and that no accurate costs can be attributed to methods of hydrocarbon extraction that have not yet been devised; nevertheless it is felt that the current stage of knowledge and feeling for the order of magnitude of costs is adequate to provide some indication of hydrocarbon potential. This potential is not considered adequate to give any optimism for the deeper waters providing substantial additions to the reserves of exploitable hydrocarbons.