Estimation of the future rates of oil and gas discoveries in the western Gulf of Mexico

Abstract

A discovery-process model was used to predict, as of January 1, 1977, the expected number and size distribution of oil and gas fields remaining to be discovered in the study area in the Gulf of Mexico and also to forecast the rate at which these fields will be discovered in the future. These predictions and forecasts were done separately for the combined Miocene-Pliocene trend area, which occupies 123,027 km/sup 2/ of the study area, and the Pleistocene trend area, which occupies 33,612 km/sup 2/. In both these areas, water depths ranged from 0 to 200 m. As of January 1, 1977, more than 2700 oil and gas fields were still expected to be discovered in both trends. These fields range in size from 0.76 million to 194.3 million barrels of producible oil equivalent. Most of these fields (94.5 percent) are predicted to contain less than 12.14 million BOE (barrels of oil equivalent) each. The rate at which these oil and gas fields will be discovered is forecasted to start at approximately 1.25 million BOE per wildcat well. This rate is forecasted to decline to about half this yield per wildcat well after the drilling of 2600 wildcat wells in the more » combined Miocene-Pliocene trend area and 1200 wildcat wells in the Pleistocene trend area. Analysis of data from areas where exploration has been relatively unrestricted indicates that the size distribution of oil and gas fields has a log-geometric form. As a result of this analysis, a new procedure was devised to estimate the form of the underlying size distribution of oil and gas fields in areas, such as the study area, where the discovery-data series has been truncated by economic factors. 13 references, 18 figures, 6 tables. « less