Triana Energy LLC and a unit of Marathon Oil Corp. will develop 82,000 acres of Marcellus Shale prospects in Fayette County, PA, and several counties in northern West Virginia, Triana said Thursday.

Charleston, WV-based Triana plans to drill four horizontal wells on the acreage this year to define optimal completion patterns. Subsequent development will involve systematically drilling 132 horizontal wells on 43 pads. Full development could involve up to 350 wells.

“We have conducted an extensive geologic assessment of this area and our evaluation is supported by the activity of other experienced operators,” said Triana President Henry Harmon. “We believe this acreage holds exceptional opportunities for large-scale Marcellus Shale development.”

The deal is the latest in a series of acquisitions and partnerships by Triana, which represent steps toward aggregating the company’s Marcellus position for development in highly prospective areas of Pennsylvania and West Virginia.

Triana also operates Marcellus development projects in Potter, Clearfield and McKean counties in Pennsylvania and Taylor and Lewis counties in West Virginia. The company was founded in 2006 by executives of the former Triana Holdings LLC, which owned and operated Columbia Natural Resources prior to its sale to Chesapeake Energy in 2005. In 2009 Morgan Stanley Private Equity took a stake in the company, allowing an expansion of its Marcellus strategy (see Daily GPI, June 3 2009).