Simulation of the Santa Barbara Field, El Tejero - Bosque Area

Abstract

ABSTRACT A numerical compositional simulation based reservoir engineering study has been made of alternative recovery processes for the Santa Barbara field, El Tejero-Bosque area. The Santa Barbara field reservoir is comprised of two productive zones, the Naricual and the Cretaceous, totaling about 2,500 feet of thickness. The reservoir is estimated to have originally contained 4.6 billion barrels of stock-tank liquids in the form of condensate in the gas zone and black oil in the oil zone, and 20.5 trillion scf of gas. This paper describes the results of a mechanistic study, designed, to examine the physical mechanisms that govern fluid hehavior, transport and production in the reservoir. The study utilized numerical models of two prototype regions, of the reservoir, representing different reservoir characteristics. The process investigated include straight depletion, pressure maintenance at 8000 psi and 6000 psi by injection of either inlet (separator) or outlet (dry) gas from the local cryogenic gas plant, re-injection of separator gas produced, and water injection into the oil column. Also were investigated the effects of completing the wells, above or below the gas oil transition zone. The hydrocarbon fluid column at Santa Barbara is highly unusual, characterized by a variation in com position with depth, being an undersaturated rich gas at the top and an undersaturated oil at the botton, both separated by a transition zone. It was determined that condensate recovery is highly sensitive to reservoir pressure performance, and independent of the composition of the gas injected Best recoveries were obtained with injection of dry gas high pressure.