The Marcellus shale may be the marquee player in the Appalachian Basin these days, but the more pedestrian Lower Huron shale is an integral member of the team.

“There is no mystery to the Lower Huron,” says Murry Gerber, chief executive officer of Pittsburgh-based EQT Corp. “We’re in massive operational mode in the Lower Huron play.”

The long-time Appalachian Basin operator holds some 3.4 million acres of leases in the basin and works three major plays: the Marcellus, Huron-Berea, and Nora coalbed methane.

A good portion of EQT’s leasehold lies in Kentucky, West Virginia and Virginia, home to many thousands of Upper Devonian-aged Lower Huron wells. For nearly a century, swarms of shallow vertical wells have produced gas from the severely underpressured Lower Huron shale.

EQT pioneered air-drilled horizontal wells in the Lower Huron, and continues to advance shale-drilling technology. Today, the company commonly drills lateral and multilateral wells in multiple zones.

Since the Appalachian operator launched its horizontal drilling program in 2006, it has drilled some 540 horizontal wells, primarily in its traditional Kentucky and West Virginia gas fields. The company groups all its low-pressure work into its Lower Huron category, including wells in the Upper Devonian Berea sandstone, Cleveland and Rhinestreet shales and the low-pressure portion of the Middle Devonian Marcellus.

The volume of gas contained in Appalachia’s low-pressure shales and tight sandstones is phenomenal. EQT’s proven, possible and probable reserves in the Lower Huron alone stand at nearly 6 trillion cubic feet (Tcf), and the Berea sandstone holds another 600 billion cubic feet equivalent (Bcf). The normal- to high-pressured Marcellus, in which EQT holds 400,000 acres, adds another 900 Bcfe in 3P reserves. In addition, all of these plays hold another 10- to 15 Tcf of potential.

A typical EQT Huron horizontal well produces 200,000 to 900,000 cubic feet per day for its first-month average, recovers 750 million to 1.5 Bcfe, and costs $1.2 million to drill and complete.

“In our Huron-Berea play, we have 2.5 target zones present on an average 80-acre drilling unit,” says Gerber. That’s a wealth of objectives, and EQT is working out the best methods to raise recovery factors in each unit.

To this end, the company has developed a “starship” pattern of branching multilaterals. On one pad, it has drilled more than 100,000 feet of laterals in each of two stacked zones.

From a two-level starship pattern, the company hopes to extract 10 Bcfe for less than $10 million, and produce at first-month average rates of 10 million a day. “The sum of the parts could be every bit as interesting as one big Haynesville well, or several Marcellus wells.”

Fracturing of multilateral wells is another area of experimentation. EQT places an external packer assembly along the main stem of a multilateral well, and each individual leg is stimulated with a single nitrogen frac.

“The results look extremely promising,” says Gerber. “The technique appears to improve our productivity and our unit costs. It’s a unique EQT innovation.”

Its first fractured, multilateral Huron well had six laterals, nearly 13,000 horizontal feet of wellbore and cost $1.8 million. Completed in the first quarter, it made an average of 850,000 cubic feet per day during its first month on production.

Next up will be fracture treatments on stacked multilaterals.

Huron drilling will dominate EQT’s activity during the next three to five years. This year, it plans 350 horizontal Huron wells, including about two dozen multilaterals.

The Huron may not get the attention lavished on the normal- to over-pressured Marcellus play, but it’s a thoroughly reliable producer, says Gerber. It can be developed at very attractive finding and development costs, and it has access to the same premium gas markets as the Marcellus play.