The Marcellus shale in West Virginia, Pennsylvania, and New York,
once thought to be played out, is now estimated to hold 168-516 TCF
still available with horizontal drilling. It has been suggested
that the Marcellus shale and other Devonian shales of the
Appalachian Basin, could supply the northeast U.S. with natural
gas. In November 2008, Chesapeake Energy, which held 1.8 million
net acres of…