Gastar Exploration Inc., an independent energy company, engages in the exploration, development, and production of oil, condensate, natural gas, and natural gas liquids in the United States. Its principal activities include the identification, acquisition, exploration, and development of oil and natural gas properties on unconventional reserves, such as shale resource plays. The company is also developing the primarily oil-bearing reservoirs of the Hunton Limestone horizontal oil play in Oklahoma; and liquids-rich natural gas in the Marcellus Shale in West Virginia. As of December 31, 2014, its principal assets included approximately 51,300 net acres in the Appalachian Basin in West Virginia and southwestern Pennsylvania, as well as 117,800 net acres in the Mid-Continent area of the U.S. in the state of Oklahoma. The company was formerly known as Gastar Exploration Ltd. and changed its name to Gastar Exploration Inc. in January 2014. Gastar Exploration Inc. is based in Houston, Texas.