The Marcellus Shale is a geologic formation of sedimentary rock that contains natural gas. Experts suggest that it may be one of the largest onshore natural gas fields in North America.
The Marcellus Shale formation is estimated to primarily stretch across portions of Pennsylvania, New York, Ohio and West Virginia. Small areas of Maryland, Kentucky, Tennessee and Virginia are also underlain by the Marcellus Shale.
Natural gas drilling in the Marcellus Shale became economically feasible for development when advanced drilling and completion techniques, such as horizontal drilling coupled with hydraulic fracturing, were developed. Chesapeake wells in the Marcellus Shale range in depth between approximately 4,000 and 8,500 feet below the surface.
Chesapeake Energy Corporation
Chesapeake Energy Corporation is the second-largest producer of natural gas, the 11th largest producer of oil and natural gas liquids and the most active driller of new wells in the U.S. Headquartered in Oklahoma City, the company's operations are focused on discovering and developing unconventional natural gas and oil fields onshore in the U.S. Chesapeake owns leading positions in the Eagle Ford, Utica, Granite Wash, Cleveland, Tonkawa, Mississippi Lime and Niobrara unconventional liquids plays and in the Marcellus, Haynesville/Bossier and Barnett unconventional natural gas shale plays. The company also owns substantial marketing and oilfield services businesses through its subsidiaries Chesapeake Energy Marketing, Inc. and Chesapeake Oilfield Services, L.L.C.​
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