Controls on Petroleum Production and Resources for the Middle Devonian Marcellus Shale, Appalachian Basin
The Marcellus Shale of the Middle Devonian Hamilton Group in the Appalachian Basin is one of numerous organic-rich Devonian shale source rocks in North America, such as the Exshaw and Bakken Formations and Woodford Shale. The Marcellus Shale is a world-class continuous source rock and reservoir with cumulative production greater than 33 trillion cubic feet of gas, 68 million barrels of natural gas liquids (NGL), and 192 million barrels of water. These volumes represent production from more than 11,700 noncommingled wells. Areas of greatest production and future potential for gas and NGL from the Marcellus Shale are within and near the northeast-trending Rome trough in Pennsylvania and northern West Virginia. Lesser production and potential are from southernmost New York, eastern Ohio, western Virginia, and Maryland. Numerous factors enhance gas and NGL production and resources in the Marcellus Shale. These include (1) brittleness based on lithofacies and mineralogical composition; (2) thickness and distribution of brittle and organic-rich shale; (3) measured thermal maturity of 1% vitrinite reflectance and greater; (4) at least 2 weight percent total organic carbon; (5) dense and complex fracturing and faulting; (6) presence of evaporite beds in the underlying Silurian Salina Group; (7) potential overpressure; (8) current depths of 1,370 m (4,500 ft) and greater; and (9) predominantly horizontal wells with laterals that are oriented to the northwest or southeast, or roughly perpendicular to the direction of maximum horizontal stress, and that cross major fault and fracture sets.
AAPG Datapages/Search and Discovery Article #90357 ©2019 AAPG Rocky Mountain Section Meeting, Cheyenne, Wyoming, September 15-18, 2019