G. Alan Petzet
Exploration Editor
A ray of hope may have appeared in the Louisiana portion of the Cretaceous Austin chalk trend after several years of expensive disappointment.
OXY USA Inc. plans to use dual leg horizontal wells to develop a fractured chalk reservoir named Masters Creek field in Rapides Parish. The state has approved four 1,920 acre spacing units, one of which contains OXY's Al Monroe well (OGJ, Dec. 12, p. 30).
The Al Monroe flowed 6.6 MMcfd of gas with 2,162 b/d of 48 gravity condensate, not oil as previously reported, through a 26/64. in. choke with 6,196 psi flowing tubing pressure from a single southward 4,000 ft horizontal lea at 14,803 ft true vertical depth. Bottomhole pressure is 13,100 psi.
OXY called Al Monroe a significant discovery and said it has additional exploration acreage blocks along the trend.
Louisiana exempts production from horizontal wells from state severance tax until all project costs are returned.
Previous Louisiana horizontal drilling in the chalk in Vernon, Avoyelles, Pointe Coupee, and West Feliciana parishes has sorely challenged operators. OXY's completion has already provided encouragement for Helmerich & Payne Inc., Tulsa, Okla., which has participated in four Louisiana horizontal chalk wells without a clearly commercial outcome.
If production holds up from the fractured Masters Creek reservoir, it could begin a new chapter in chalk exploitation east of Texas.
OXY'S PROGRAM
OXY placed the Al Monroe on production on Nov. 1 after constructing extensive surface facilities, drilling a saltwater disposal well, and laying a 7 mile, 10 in. gas pipeline. The fluids and gas handling equipment is of modular design for expansion as development wells are added. An amine unit strips small volumes of carbon dioxide from the raw gas.
The well, flowing at an operator determined maximum efficient rate, has produced about 70,000 bbl of condensate and 220 MMcf of gas through early December, said Keith Jordan, southern region geological supervisor, Houston.
The medium radius well, in 30-1n-2w, 20 miles southwest of Alexandria, was drilled by an Ensco Drilling Co. rig equipped with top drive. OXY ran slotted liner for completion. Lower chalk thickness averages about 100 ft out of a gross chalk thickness of nearly 2,000 ft.
OXY holds 10017, working interest and controls about 30,000 surrounding acres. OXY plans to closely monitor production from the discovery well before kicking off its development plans.
The first development well is to have dual opposing 4,000 ft legs north and south from the surface location, Jordan said. Cost is estimated at $5-7 million, depending on configuration.
It is to be spudded in second quarter 1995. Helmerich & Payne holds a 50% working interest with OXY in acreage west of the Masters Creek field units.
K.P. Ducote, vice-president domestic exploration, Bakersfield, Calif., said OXY is considering exploratory drilling in 1995 on other acreage blocks within the Louisiana Austin chalk trend.
Masters Creek field, discovered in 1979, produced small volumes of chalk gas and condensate from one vertical well.
Meanwhile, OXY has completed five single leg horizontal oil wells in Eocene Wilcox at about 2,1 00 ft in Olla field of La Salle Parish to the north. The company plans to continue active development there in 1995 using vertical and horizontal wells.
BUOYING H&P
Allen Braumiller, H&P vice-president exploration, termed OXY's completion "impressive" and hopes for positive early performance.
Braumiller calls Masters Creek a higher pressure, gassier, and more expensive area than North Bayou Jack field in Avoyelles Parish, where H&P and others have fought the chalk.
OXY's 1,920 acre units at Masters Creek compare with 960 acre units H&P and others established at North Bayou Jack field about 30 miles east in Avoyelles Parish (see map, OGJ, July 6, 1992, p. 88).
Cliffs Oil & Gas Co., Houston, H&P, and others completed the IA Roy Martin in 1991 for 2,566 b/d of oil from the chalk at 15,339 ft TVD. It produced 207,000 bbl of oil from a 2,030 ft leg before production ceased, possibly due to hole blockage by accumulation of an impermeable mix of produced chalk fines and barite in the curved section.
A group of companies including H&P re-entered 1A Martin and encountered pressure immediately. The group restored IA Martin to production at a marginal rate.
H&P and others drilled the horizontal I Arbor 2 miles west of 1 A Martin and established only marginal chalk production.
Further west, Sonat Exploration Co. and H&P tried the IC Sonat Minerals, a marginal chalk oil discovery of North Haddens field in Vernon Parish.
Then Union Pacific Resources Co. and H&P teamed to drill the horizontal 1 LaCour, in 41-3s-8e, Pointe Coupee Parish. Completed earlier this year, it has produced 44,214 bbl of oil and 22.2 MMcf of gas from chalk, according to Petroleum Information Corp. The well is still producing at a marginal rate, but performance may not justify further development, Braumiller said.
UPRC this year temporarily abandoned another chalk horizontal attempt, 1 Spillman, in West Feliciana Parish, at TD 17,388 ft, PI reported.
Copyright 1994 Oil & Gas Journal. All Rights Reserved.
