Abstract: Producibility and Characteristics of Oil and Gas Fields with Deepwater Clastic Reservoirs

Stephen P. J. Cossey, Thomas M. Byrd, Richard J. Howarth

Prediction of producibility prior to drilling has traditionally relied on local analog studies and hypothetical engineering models. An alternative approach focuses on geological and engineering characteristics from a global dataset of 179 producing fields.

Empirical models have been developed to predict field peak production rates and recovery factors in turbidite reservoirs. These models were developed using ridge regression and regression tree techniques applied to the analog dataset. Fifty engineering and geological parameters for each field were analyzed. These parameters include information on geologic and tectonic setting, age, producing depths, rock properties, fluid properties and producing characteristics. Empirically, recovery factors are mostly dependent upon hydrocarbon phase, tectonic setting, trap type, reservoir age, depth, and temperature. These are geological characteristics that are generally predictable prior to drilling. Field peak production rates (average daily rate during the peak year of production) are strongly ependent upon tectonic setting, permeability and the estimated ultimate recovery (EUR) of the field. The study also examined the worldwide variability of average well flow rates. In turbidite reservoirs, the highest average well flow rates (total wellspeak flow rates) are in the North Sea with successively lower rates in offshore Brazil, Gabon and the Gulf of Mexico.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994