Marcellus Shale is bigger than estimated

By TOM KANE

REGION - A geologist says the Marcellus Shale of the Appalachians could yield seven times as much natural gas as he earlier estimated, and could meet the entire nation’s natural gas needs for at least 14 years.

Penn State University geoscientist Terry Engelder now estimates that 363 trillion cubic feet of natural gas could be recovered over the next few decades from the 31 million acres of the Marcellus region, which includes southern New York, Pennsylvania, West Virginia and eastern Ohio. The new estimates are based on numbers from Chesapeake Energy Corp., one of the largest stakeholders in the Marcellus area, Engelder said.

Late last year, he and geologist Gary Lash of the NY State University at Fredonia originally estimated that the yield could be as much as 50 trillion cubic feet of natural gas.

“Geologists are still attempting to size the Marcellus play,” Engelder said. “We don’t know yet how much gas is there and how much can be recovered.

Engelder, a professor of geologic science, has studied Appalachian shale formations for more than 30 years. He presented his new estimates at a conference in Pittsburgh on October 30 sponsored by the energy information firm Platts, a division of McGraw-Hill Company. The conference was reported in the Pittsburgh Tribune-Review.

At the Pittsburgh meeting, Oklahoma-based Chesapeake Energy said each square mile in the Marcellus shale area could contain 30 billion to 150 billion cubic feet of gas.

In computing his new estimate, Engelder said he used an average of that range, 90 billion, to figure that the entire 31 million-acre region might hold 4,359 trillion cubic feet of gas. If 30 percent of that gas were brought out of the ground as Chesapeake anticipates, he said, that would be 1,307 trillion cubic feet from the entire region.

Producers working in the area will provide a more accurate picture over time, he said, adding that he was trying to keep his estimates conservative.