Deeper wildcatting under way in two New Mexico areas

Aug. 23, 1999
The volume of E&P activity in the San Juan basin overshadows its maturity.

The volume of E&P activity in the San Juan basin overshadows its maturity.

Deeper exploration is far from dead in northwestern New Mexico. A group led by Burlington Resources Oil & Gas Co., Houston, is conducting an exploration program aimed at Pennsylvanian zones deeper than most production in the San Juan basin.

Far to the southeast, an independent drilling its second rank wildcat is determined to find gas in Cretaceous, which produces almost all of the gaseous hydrocarbons in the San Juan basin. It plans to deepen a wildcat to 15,000 ft at a site southwest of Albuquerque in the Albuquerque basin.

Pennsylvanian program

The Burlington group is pressing efforts to discover deep production in the San Juan basin, where it is using 3D seismic data to help define targets.

The group's most recent drill site is the 1 Mudge Com, in 23-31n-11w, in San Juan County near the town of Aztec. The federal notice of staking does not carry a depth objective, but the well is understood to be a deep Pennsylvanian exploratory test.

The same group previously staked the 2 Vasaly Com, in 22-30n-11w, 7 miles south of the 1 Mudge. It is projected to 13,400 ft.

These sites are near the group's 2 Marcotte, in 8-31n-10w. That well flowed 750 Mcfd of gas and 168 b/d of water with 110 psi FTP on a 48/64 in. choke from an undisclosed zone of Pennsylvanian age, IHS Energy Group reported.

These Burlington operated wells are less than 20 miles east-southeast of Barker Dome/Barker Creek field, discovered in 1945, the nearest production from Pennsylvanian. That field, in La Plata County, Colo., and San Juan County, N.M., has produced well over 100 bcf of gas from Pennsylvanian Paradox at 8,900-9,300 ft.

Conoco Inc., BP/Amoco, and Devon Energy Corp. are partners with Burlington. Burlington acquired 350 sq miles of 3D seismic last year in the basin, where early this year it held rights to 815,000 gross acres in the Pennsylvanian formation.

Albuquerque basin

Meanwhile, a little known operator that is a large fee-simple landowner in New Mexico is wildcatting for Cretaceous gas in the Albuquerque area.

Twining Drilling Partners No. 2 LP, with a field office in Albuquerque, drilled a rank wildcat in Socorro County to 8,400 ft in the Tertiary Santa Fe Group earlier this year and cemented 7 in. casing to TD. Now it plans to re-permit one of its wells to 15,000 ft to test Cretaceous, said Ronald L. Rutherford, vice-president. Operations are to resume in October or November. Twining is based in Baltimore.

Twining's wildcat, the 2 NFT, is in 28-4n-1e, southwest of Belen, N.M. The site lies between the Rio Grande and Rio Puerco rivers about 40 miles southwest of Albuquerque.

This drill site is 80 miles southeast of nearest San Juan basin production and is on a 60,000 acre drill block traversed by El Paso Natural Gas Co. and Transwestern Pipeline Co. gas lines. As to well results, Rutherford would say only that drilling so far generated enough interest to pursue drilling below the area's Tertiary fill.

He noted that other prominent explorers have worked the general area, with rank wildcats drilled in Sandoval and nonproducing Bernalillo, Valencia, and Socorro counties. Among the companies are Vastar/Davis Petroleum Corp. and Shell Oil Co., which drilled to about 22,000 ft in the area in the 1970s without success.

Davis drilled the 1 Angel Eyes, in 19-4n-1e, Valencia County, to 8,074 ft in 1996. It was abandoned with no tests reported.

Twining drilled a 7,441 ft dry hole at the 1 NFT, in 33-5n-1e, Valencia County, in 1997. That is about 4 miles north of its current wildcat.

Lozinsky and Tedford, in New Mexico Bureau of Mines & Mineral Resources Bulletin 132, published in 1991, note that Exxon predecessor Humble Oil & Refining Co. drilled to 12,690 ft, into Upper Cretaceous, at the 1 SFP well in Valencia County just west of the Rio Puerco in 1953 without success.

They called the Albuquerque basin "one of the largest of the structural and physiographic basins that comprise the Rio Grande rift." The publication provides a lengthy discussion of the Santa Fe Group.

Mature and busy

The volume of activity in the San Juan basin overshadows its maturity.

Most gas production comes from Cretaceous Fruitland (including coal), Pictured Cliffs, Mesaverde, and Dakota at 1,000-8,500 ft.

Coalbed methane drilling has matured in the San Juan but was a major force there the past 10 years. Burlington said it hiked its net gas production by an average compound rate of 15%/year during that time to 840 MMcfd at yearend 1998, about half of which was coalbed methane.

The big program at present is Cretaceous Mesaverde infill drilling on 80 acre spacing, approved earlier this year (OGJ, Mar. 15, 1999, p. 72). Operators initially developed Mesaverde on 320 acres in the 1950s.

Burlington also has a large recompletion program under way tapping gas in 1,200-1,500 ft of Cretaceous Lewis shale/Chacra formation. This zone, a major source rock in the basin, lies just above Mesaverde.

Burlington said the first 29 recompletions, effected in 1998, averaged 300 Mcfd of gross production increase. It calculated the cost of adding the Lewis reserves in those wells at about 30c/ Mcf.

The company said the program could run 5 years and involve more than 1,000 recompletions.

In the northeastern part of the basin, drilling continues to expand to tap gas reserves in Paleocene Ojo Alamo. Mallon Resources Corp., Denver, is the main operator in this shallow play in northwestern Rio Arriba County (see map, OGJ, Apr. 27, 1998, p. 77). Williams Production Co., Tulsa, and Edwards Energy Corp., Denver, have staked locations following the play to the northwest.

In the southeastern part of the basin, a small play for oil in dune-like features in the Jurassic Entrada is ebbing and flowing with oil prices. It has involved only a few wells but could grow wider in scope if oil prices stay high enough long enough.