Performance of Jay/LEC Fields Unit Under Mature Waterflood and Early Tertiary Operations

Abstract

Secondary oil recovery for the Jay/Little Escambia Creek (LEC) Fields Unit will exceed initial estimates by 27 X 10 6 bbl [4.3 x 10 6 m 3 ] because of innovative reservoir management based on a comprehensive surveillance program and detailed reservoir description data. Infill drill wells have accounted for 76 X 10 6 bbl [12 X 10 6 m 3] of oil production. The mature waterflood was phased into a tertiary recovery project in 1981, and early performance is generally consistent with the planning study, which predicted that 47 X 10 6 bbl [7.5 X 10 6 m 3 ] of tertiary oil will be recovered.

Development of mature oil fields — A review

“…Another cost effective reservoir development practice was to improve the volumetric sweep efficiency through the realignment of the injection and production wells (Zambrano et al, 1992). Surveillance of the secondary and tertiary Schiltz et al, 1984;Rowe et al, 1982 Twofreds (Delaware) Unit ( Christian et al, 1981;Langston and Shirer, 1983;Lawrence et al, 2002Garber (1916 CO 2 5-spot pilot ( Schiltz et al, 1984 recovery through performance monitoring, data acquisition and vertical conformance monitoring was reported to be an effective management strategy for mature fields (Stiles and Magruder, 1995). Reservoir characterization attempts for developing mature fields are also applied commonly.…”

Reservoir characterization of the Smackover Formation in southwest Alabama. Final report

“…A gas-injection program was commenced in Jay-LEC fields in 1981. Estimations of remaining oil after waterflood were 355 million barrels of oil and 13 percent of this oil (47 million barrels) could be recovered by implementing the water-alternating-gas (WAG) program (Langston and Shirer, 1985). WAG operations began in 1981 and methane gas was used initially.…”

“…A total of 2 billion cubic feet of methane gas was injected into the reservoir until a nitrogen source was developed. Water was injected into the reservoir along with the methane and nitrogen (Langston and Shirer, 1985).…”

“…Infill drilling in Jay-LEC fields was an important part of the waterflooding project (Langston and Shirer, 1985). Modeling studies indicated that the 160-acre spacing was inadequate to effectively sweep low-permeability areas.…”

Experimental and molecular modelling study of the three-phase behaviour of (propane+carbon dioxide+water) at reservoir conditions

“…From a thermodynamic point of view the presence of water means that a third phase will typically coexist with the oil-rich and CO 2 -rich phases. It is generally understood that reservoir conditions mean high temperatures and high pressures (characteristic temperatures for diverse oil reservoirs may vary from 300 K to 410 K with initial conditions of pressure from 10 MPa to 50 MPa [5][6][7][8][9]), although such pressure conditions will obviously vary during the life of the reservoir. The essential input for CO 2 -EOR processes from phase equilibria measurements is however limited to pressures on the bubble-curve locus of hydrocarbons with CO 2 in the presence of water.…”