Drillers set sights on shale reserve deeper than the Marcellus
Another underground strip of shale in Pennsylvania, much deeper than the Marcellus formation, is drawing attention from natural-gas drillers.
Utica shale has potential, like Marcellus, to become a major fuel resource. The rock layer stretches far beyond the edges of the Marcellus, covering most of Pennsylvania, New York and West Virginia, along with eastern Ohio and parts of other states.
"A number of companies are taking a careful look at this shale, and in eastern Ohio there's been a fair amount of leasing" for well development, Penn State University geosciences professor Terry Engelder said Monday.
Consol Energy Inc. drilled a Utica shale well last year in Belmont County, Ohio, that generated 1.5 million cubic feet of gas over 24 hours -- impressive for a well where production wasn't stimulated, spokeswoman Laurel Ziemba said.
"It's actually higher than the rate from any of our vertical Marcellus wells" where production was triggered, she said. Cecil-based Consol plans to spend $35 million this year to drill about six exploratory Utica wells.
Range Resources Corp., a Fort Worth company with Appalachian offices in Cecil, is drilling in the Utica formation. Range drilled the first commercial horizontal well in the Utica formation in Southwest Pennsylvania, spokesman Matt Pitzarella said.
Chevron Corp. completed its $4.3 billion acquisition of Atlas Energy Inc. of Moon last week, giving the energy giant access to 623,000 acres of Utica shale resources. The company isn't specifying its plans for Utica shale, Chevron spokesman Nate Calvert said.
The Marcellus shale formation that sparked a rush of drillers to Pennsylvania and other Appalachian states averages 7,000 feet deep, and the older, thicker Utica layer runs 2,000 or more feet below that. The black Utica shale, 500 feet thick in places, dates 440 million to 460 million years.
Some geologists estimate the Marcellus formation has 50 trillion cubic feet of recoverable gas, enough to supply the East Coast for 50 years.
Although it hasn't been studied enough to determine its potential, Utica shale has shown the ability to support commercial gas production, a report in website geology.com said, and depending on how much of it might yield fuel, it could be larger than any known gas field.
Gas producers could drill down and then horizontally and inject high-pressured water, sand and chemicals to fracture the shale and free gas deposits, just as they do in Marcellus fields, Engelder said.
The additional depth isn't a hindrance, he said. "There's the Haynesville formation in Louisiana, where drillers are going as deep as 13,000 feet using the same technology," Engelder said.
Rock formations in the Appalachian basin tend to be thickest in the east and thinner toward the west, the geology.com report said. The Utica is about 7,000 feet below the Marcellus in central Pennsylvania, but less than 3,000 feet below it in eastern Ohio. In Western Pennsylvania, the Utica layer runs 11,000 to 12,000 feet deep.
Although the two gas-producing shale layers overlap, production companies could focus on different regions.
That's because certain parts of each shale formation will yield more fuel, based largely on temperature and pressure histories, Engelder said. His analogy: Shale that remained cooler, like a piece of underdone toast that won't melt butter, won't yield much gas, nor will a too-hot formation that burned off its gas, like blackened toast.
Rock that reaches 190 degrees Fahrenheit generates oil and some gas, he said. The top heat for creating, and not destroying, gas is 480 degrees.
Much of the Utica shale in that ideal pressure and temperature range stretches from the northwest Pennsylvania town of Titusville, where an oil boom began 150 years ago, to Columbus, Ohio, Engelder said.
Tom Murphy, co-director of Penn State's Marcellus Center for Outreach and Research, said Utica gas could have a higher British thermal unit, or BTU, content than Marcellus gas, making it more marketable.
"The southeastern part of Ohio right now is being explored for Utica shale gas," Murphy said, and some work is occurring in West Virginia. Landowners who lease mineral rights typically strike deals for producers to drill "all the way down" past the Marcellus to other layers of rock, he said.
Range Resources plans to drill a few more wells this year in the Utica and Upper Devonian shale layer, which is above the Marcellus. Gas producers potentially could drill multiple layers of wells in the future, all from the same spot, Pitzarella said.
"The Utica and Upper Devonian may combine to be as large as the Marcellus" in terms of recoverable gas, he said.
Show commenting policy
TribLive commenting policy
You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.
We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.
While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.
We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers.
We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.
We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.
We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.
We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.
- PennDOT team decides what spells trouble on vehicle license plates
- Pirates get journeyman Ishikawa off waivers; outfielder Marte injured
- Alvarez homer triggers winning outburst for Pirates
- Film shares tale of Pittsburgh man who turned disability into career
- Woman shot at Kennywood Park in ‘freak accident’
- Apple Hill Playhouse takes on an updated ‘Snow White’
- Man charged with passing counterfeit bills at Rivers Casino
- Westmoreland County on pace to surpass record for drug-related fatalities
- Don’t remove history’s lessons
- United States takes down Japan, wins third Women’s World Cup
- Bookings for August Wilson Center climb, but permanent board yet to be set