Additional Plays: Drillers Testing Other Shale Formations Above and Below the Marcellus Strata

Washington PA Observer Reporter
7 June 2010
By Michael Bradwell, Business editor
mbradwell@observer-reporter.com

Pennsylvania's geology has the potential of delivering natural gas from a variety of shale formations beyond the Marcellus strata, a geologist said last week.

But Dr. Terry Engelder, professor of geosciences at Penn State, who has spent 30 years studying the Marcellus, said the "super giant" shale formation is in no danger of losing its position as one of the world's largest gas fields.

"It's not just the Marcellus," Engelder acknowledged when asked about recent announcements by two drilling companies working in Pennsylvania that test wells have been completed in two other shale formations which lie above and below the Marcellus strata.

Range Resources spokesman Matt Pitzarella said the company has drilled some test wells into the "Rhinestreet" formation, which is part of the Upper Devonian shale that sits about 1,000 feet above the Marcellus strata. The company has also tested the depths below the Marcellus where the Utica formation lies.

"The tests were encouraging enough that they could be stand-alone shale plays in their own right," he said.

In Northeastern Pennsylvania, Cabot Oil & Gas Corp. told analysts last year it had drilled a successful horizontal well through the Purcell Limestone sandwiched between two layers of its Marcellus acreage.

Engelder noted that all of the shale formations can yield gas. He added that while reports of test wells in the other strata are just now emerging in Pennsylvania, some of them have been drilled in other parts of the country for some time.

He said Pittsburgh-based EQT has been drilling in Upper Devonian shale in Kentucky's Big Sandy play for some time.

The emergence of the other shale formations in Pennsylvania are so new, that no one yet knows their impact on the gas exploration industry or their economic impact.

"It's just really early now," Pitzarella said. "No one's really given much detail in terms of production data."

When the authors of a Penn State study detailing the projected economic impacts of the Marcellus Shale gas play released an update two weeks ago, they noted that their report did not consider development of other shale formations that exist above and beneath the Marcellus.

There are also some regulatory factors that could affect the future extraction of gas from shale.

Drillers face the increased scrutiny from the Environmental Protection Agency, which is studying the effects of water pollution used in hydraulic fracturing used to release the gas from the tight shale formations. There are also several legislative proposals in Harrisburg to enact a severance tax on gas extracted from the Marcellus shale.

Both Engelder and Pitzarella said the other shale formations could be places that drillers could return to after the Marcellus acreage is more fully developed.

Despite the promise of gas yields from the other formations, Pitzarella said Range still views the Marcellus as its primary goal.

"The Marcellus is the best of the best" formations, he said.