Appalachia's Trenton Black River interest grows.
The Trenton Black River play in New York and West Virginia in the northeastern United States might unlock the tremendous natural gas potential of the deep Appalachian Basin that experts predict, or it might be the target of lofty dreams triggered by one 50 MMcf/d well fluke and a hush-hush atmosphere.
What little publicity exists surrounds the Ordovician Trenton Black River fractured carbonate play that occurs in much of the northeast from Tennessee to Ontario, specifically on the Rome Trough from southern New York through Pennsylvania and West Virginia into Kentucky. The target is fractured lime and dolomite at depths from around 7,600ft (2,318m) in the north to more than 10,000ft (3,050m) in the south.
One trigger for the interest was a US $32 million deep-Appalachian exploration program started by Columbia Natural Resources in 1997. One of the results of that program was the company's successful Trenton Black River field program from 1998 through 2000. Probably its best field, and earliest, was Glodes Corners field in Steuben County, N.Y.
That field was discovered in 1985, but it wasn't brought into production until 1997. Initial production on the discovery was 935 Mcf/d, and the best well recorded by IHS Energy Group in its Petroleum Frontiers, Vol. 17, No. 1, report was 3.29 MMcf/d. That's a good well for the area but not good enough to spark a drilling boom in an area abandoned by major oil companies.
Overall, Columbia Natural Resources drilled 32 wells in the New York campaign with the help of a seismic survey. At the end of the year, it called 1999 the most successful year for exploration in its history.
The key that opened the door to would-be wildcatters, however, was Columbia Natural Resources' Frederick C. Parker et al. wildcat completed in June 1999 in Roane County, W.Va., to the Trenton Black River. It showed an initial potential of 50 MMcf/d with shut-in tubing pressure of 5,750 psi and bottomhole pressure of 6,600 psi from an openhole section between 9,792ft and 10,271ft (2,987m and 3,133m).
The company hooked the well into a sales line at 7.3 MMcf/d and followed up with confirmation wells in the new Cottontree field. Information subsequent to the discovery well has been tight.
More than 18 months after that discovery, curiosity is high. "During the past 2 weeks, I've taken more calls than I usually take in a month, and most of them are about the Trenton Black River," said David Matchen, petroleum geologist with the West Virginia Geological and Economic Survey in late December.
A lot of people are interested from outside the Appalachian Basin, he said. Among them, Martin Twist Energy Co. LLC of Louisville, Ky., has accumulated 30,000 acres of leases in Roane, Ritchie, Wirt, Woods and Calhoun counties in West Virginia, and it was joined by Solana Petroleum Corp. of Calgary, Alberta. That company brought EXP Resources Ltd. into the team, and they plan to shoot 28 miles (45km) of seismic.
The group drilled one well 3,000ft (915m) from Columbia's third Cottontree field well, starting in January 2000 through a completion attempt in August. The operators had to flare that well several times in spite of a mud weight of more than 10 lb/gal, but they aren't talking about the results of the drilling.
Another team consists of Trans Energy Inc., Jayhawk Resources LLC and International Oil & Gas Inc. with 5,000 acres and plans for seismic.
Plenty of problems inhibit the play. One is tradition. Much of the development in the Appalachian Basin is done by "closeology." Traditionally shallow wells were so cheap to drill it made more sense to step out with wells until the hydrocarbons stopped than to shoot seismic. Not much seismic exists. Geologists have only a hazy idea of the boundaries and shape of the Rome Trough as it passes through Pennsylvania, for instance.
Matchen thinks the play will be big. "People seem to be looking for dolomite along a fault plane. It's going to be big through West Virginia, but it's hard to tell how big this will be until we get more wells completed. Although New York has 123 Trenton wells, West Virginia has only 42 wells even to the permit stage, and only two wells have production records.
This is going to be a technology play, Matchen predicted. That means seismic and modeling and an intense search for structural features like the Vineyard Ridge anticlinal nose that probably caused the fracturing under the Parker well.
At this point, no one is sure where the play will be going, but many feel, or hope, this will be the starting point for a drilling bonanza in the Appalachian Basin.