Oryx Energy Co., Dallas, at or near the top among U.S. operators committed to horizontal drilling, is expanding its operations in the Cretaceous Austin chalk trend of South Texas.
Industry is harvesting big oil flows in the trend with horizontal wellbores.
In its latest move, Oryx has taken a farmout from Snyder Oil Corp., Fort Worth, covering 38,500 net acres and involving a horizontal drilling project in the trend. Oryx can earn half of Snyder's interest in the acreage by paying certain costs, including those for seismic work and drilling.
In other Texas horizontal drilling operations:
- Winn Exploration Co., Eagle Pass, Tex., tested a horizontal Austin chalk well with a calculated flow of 19,560 b/d of oil in Zavala County's Pearsall field. Texas Railroad Commission officials said 25 Leta J. Glasscock, owned 100% by Winn, is the biggest well completed in the state in recent history.
- Service Fracturing Co. (Serfco), Pampa, Tex., is preparing to complete the first horizontal hole drilled into another wellbore in West Panhandle Carson field.
ORYX SNYDER AGREEMENT
Oryx will operate the horizontal drilling program in Maverick and Dimmit counties.
Wolverine Exploration Co., Fort Worth, formerly was the operator and still holds a 29.1667% interest in the project. Snyder's interest prior to Oryx's fulfillment of farmout obligations is 43.75%. Private investors own the remaining interest.
Snyder said seismic work will start soon, and more drilling is to begin in fourth quarter 1990 or early in 1991. Snyder is the largest working interest owner on the 88,000 gross acre Halsell Ranch block involved in the farmout.
Oryx Chairman Robert Hauptfuhrer underscored his company's heavy commitment to horizontal drilling early this year, long before the trade with Snyder surfaced. He said Oryx will drill more than 100 horizontal wells in the U.S. this year, including 85 in the Austin chalk trend (OGJ, Jan. 15, p. 28).
Snyder Chairman John Snyder said, "Oryx's unparalleled experience in horizontal Austin chalk drilling substantially enhances the project's potential. In addition, through working closely with Oryx and Wolverine in the chalk, we can increase our expertise in horizontal drilling technology for application in other areas."
Part of that application could take place in the Cretaceous Niobrara trend of northern Colorado and Southeast Wyoming. Snyder is seeking to form a joint venture there to explore 140,000 net acres of its 220,000 net acre leasehold.
Acreage under joint venture consideration lies directly south of Cowan Oil's horizontal drilling success in the Niobrara in Silo field. In this area, Niobrara, like Austin, is a vertically fractured chalk.
Snyder plans to operate this venture, which it says is likely to use horizontal drilling. It plans to begin drilling there late this year if the joint venture shapes up.
LATEST ORYX PRODUCERS
Oryx last week reported two more successes in the Austin chalk, where a pair of discoveries flowed at a combined rate of more than 1,800 b/d of oil and 1 MMcfd of gas.
The company's 1 C. Jasik flowed 1,084 b/d and 643 Mcfd through a 34/64 choke with 340 psi flowing tubing pressure from pay zones between 6,152 and 10,021 ft measured depth. Horizontal displacement is 3,822 ft.
Oryx said the well, in Dimmit County about 21/2 miles north of Big Wells, extends the potential for Austin chalk production to the western edge of its acreage in the Big Wells area. Site is 21/2 miles southwest of Oryx 1 Heitz, the company's best horizontal well, with 275,000 bbl cumulative production since its completion last fall.
The second discovery, 1 D. Cross et al., flowed 728 b/d and 359 Mcfd through a 28/64 choke with 220 psi flowing tubing pressure from pay at 7,092-9,463 ft measured depth. Horizontal displacement is 2,713 ft.
Oryx began acquiring leases in the Pearsall area late in the 1980's. Its 100% interests cover about 180,000 acres.
Cumulative production all Oryx horizontal Austin chalk wells amounts to more than 2 million bbl.
WINN'S BIG WELL
Winn 25 Glassock also flowed an estimated 11.7 MMcfd of gas, based on a gas:oil ratio of 500:1 and tests at offsetting wells.
Tom Melville, TRC district engineer, said oil and gas flowed through tubing and casing during a 3 hr test.
Three chokes were set on tubing and another on casing for the test. Tubing choke sizes on a wing valve assembly were 15/8 in. and 48/64 in. A 3 in. choke was set on the top of the tree, and a 1 in. choke was mounted on casing. Flowing tubing pressure was 95 psi, casing pressure 320 psi.
Drilled with a medium radius borehole to 9,347 ft measured depth, the well has a displacement of 3,272 ft.
Production rates for 25 Glasscock far surpass the flow at Meridian Oil Inc. 1H E.E. Smith in Gonzales County, 7 miles south of Nixon, Tex., previously the largest Austin chalk well. It flowed 12,254 b/d of oil, 3,032 b/d of water, and 4.9 MMcfd of gas (OGJ, June 11, p. 17).
SERFCO WELL
Serfco's 14S horizontal wellbore in the Texas Panhandle starts at the wellbore of the company's No. 14 vertical well. It has a liner set through 94 ft of Permian Brown dolomite and 871 ft of horizontal hole.
Serfco Pres. Jerry H. Guinn said the well will be completed with a technique he developed and will market as Low Pressure Reservoir Alternative Completion. Among other things, it is designed to improve control of stimulation through one or both connected wellbores.
Acidizing, fracturing, and testing will take about 90 days.
The well is on a tract Serfco bought in April 1989 that contains 181 stripper oil wells. It said production has more than doubled since it began hydraulic fracturing and selectively acidizing some of the wells.
Serfco last March acquired another package of West Panhandle field leases consisting of 3,250 developed and 6,000 proved undeveloped acres. The leases contained 325 wells, of which 177 were producing.
Copyright 1990 Oil & Gas Journal. All Rights Reserved.
