Edwin E. Sticker
Mississippi Office of Geology
Jackson
Bay Springs field is in western Jasper County, Miss., about 1 mile east of the town of Bay Springs (Fig. 1).
The field was discovered in 1965 after seismic work conducted by Shell Oil Co. led to the drilling of the Shell 1 C.E. Brown in 27-2n-10e.
After initial completion attempts in Jurassic Upper and Lower Smackover yielded unsatisfactory results, a completion was made in a Jurassic Lower Cotton Valley sand later to be named the Bay Springs sand (Fig. 2).
The well was officially tested through perforations at about 14,500 ft in the Bay Springs sand at a rate of 585 b/d of oil through a 10/64 in. choke with a flowing tubing pressure of 1,850 psi. The gravity of the crude was 47.5 with a GOR of 630:1.
It is interesting to note that the operator initially considered plugging and abandoning the well due primarily to the asphaltic nature of the oil in the sidewall cores.1
STRUCTURE, STRATIGRAPHY
The Jurassic structure at Bay Springs field is a simple anticline with an increased rate of dip on the southern or basinward flank (Fig. 3).
Structural closure ceases to exist in the Lower Cretaceous section, indicating that major salt movement stopped during the Jurassic period.
The majority of the reservoir rocks encountered thus far are quartz sandstones ranging from Upper Cotton Valley through Smackover. The only exceptions are occasional dolomitic zones in the Smackover that are thin and have contributed minimal production.
DEVELOPMENT HISTORY
From 1965-90 companies drilled 34 Jurassic tests on the Bay Springs structure.
Although eight of these wells were plugged and abandoned, the primary field operators, Shell and the former Skelly Oil Co., drilled only three unsuccessful wells.
Based on production reports issued by the Mississippi State Oil & Gas Board, the original 26 producing wells have produced a combined cumulative of 33 million bbl of oil and more than 18 bcf of gas.
Esenjay Petroleum Corp., Corpus Christi, during 1990 drilled the 2 I.B. Alexander, in 27-2n-10e, as a Smackover test in an attempt to gain both additional reservoir rock and structure to the original Shell 1 C.E. Brown.
The initial completion of the 2 I.B. Alexander was in a thin Lower Smackover dolomite.
After the well produced slightly more than 10,000 bbl of oil in 4 months, Esenjay recompleted it in a Jurassic Haynesville sand at a rate of 898 b/d of oil and 1.78 MMcfd of gas through a 14/64 in. choke with 2,743 psi flowing tubing pressure.
This sand, locally called the McNeal sand,2 has produced almost 3.5 million bbl of oil and 5.4 bcf of gas at McNeal field 4 miles northeast of Bay Springs field (Fig. 1).
The McNeal sand, listed at Bay Springs field as the Buckner oil pool by the state oil and gas board, had previously been produced only in the field discovery well from a subsequent recompletion. The 1 C.E. Brown yielded about 150,000 bbl of oil and 193 MMcf of gas from the McNeal sand before watering out.
At this writing eight wells have either been drilled or deepened to evaluate the new Haynesville potential, with only one recorded dry hole (Fig. 4).
It has been reported that two of these wells, the Esenjay 3 Fender in 27-2n-10e and the J-O'B Operating Co. 1 Buckley Heirs in 34-2n-10e, are being evaluated for deeper Smackover-Norphlet potential.
The latest published production report issued by the oil and gas board indicates that Esenjay had four wells on production in the McNeal sand as of November 1991.
During that month 1 G. Windham in 35-2n-10e, 2 T.M. Sims in 34-2n-10e, 3 C.E. Brown in 27-2n-10e, and 2 I.B. Alexander produced 82,801 bbl of oil and 114.564 MMcf of gas. The latter three wells each averaged 826 b/d of oil and 1.1 MMcfd of gas.
Although these reports indicate that no formation water has yet been produced, it is the writer's opinion that these relatively high production rates will result in premature water encroachment.
CONCLUSIONS
Based on reservoir parameters furnished by Esenjay, it is calculated that if produced properly the McNeal sand should yield from primary recovery almost 2 million bbl of oil.
Additional reserves are probable in the Smackover-Norphlet interval on the western and southwestern end of the field.
The development history of Bay Springs field serves as an example of the potential yet to be uncovered in numerous mature oil and gas fields of Mississippi.
REFERENCES
- Varnado, N.L., consulting geologist (previously with Shell Oil Co.), personal communication, 1981.
- Mississippi Oil & Gas 1990 annual production report, Mississippi State Oil & Gas Board.
- Barton, C.A., McNeal Field, Jasper County, Miss., A Unique Jurassic Oil Accumulation, GCAGS Transactions, Vol. 25, 1975, pp. 80-84.
- Mississippi Oil & Gas November monthly production report, Mississippi State Oil & Gas Board, 1991.
Copyright 1992 Oil & Gas Journal. All Rights Reserved.
