Engelder estimates Marcellus gas to be more than 600 API at the bottom 30 to 40 feet of the structure, compared with 300 API at the sweetest depth of the Haynesville shale play in northwestern Louisiana.

?Lower Huron and Marcellus Devonian gas shales are invigorating the Appalachian Basin, the world’s original producing province.

Despite a tough economy and a cautious industry, this super-giant gas field in the Appalachian Basin remains highly promising. Water and environmental issues must be addressed.