It’s nice to have one in the bag, especially when that discovery includes the most prolific shale test in North America.

Apache Corp. is estimating a net 48 Tcf in recoverable gas from its 430,000 acres in the Liard Basin, a geological natural gas treasure trove in northeast British Columbia that spills across the borders into the Northwest and Yukon territories.

Natural gas may be the wrong answer at the moment with prices below $3 per Mcf, stubbornly rising production, and nagging forecasts for a multiyear low-price environment, but Apache’s Liard discovery positions the company for the transformation under way as an isolated North American natural gas market begins globalization.

Apache’s Liard Basin Lower Besa River First Black shale discovery is the westernmost of a handful of headline Canadian gas basins that include the Horn River, the prospective Cordova Embayment and the Montney shale. That 48 Tcf in the Liard (out of 201 Tcf gas in place) compares favorably to original estimates of 49 Tcf recoverable from the Marcellus ( now ranging up to 84 Tcf ) and 60 Tcf recoverable from the Haynesville.

So yes, Apache’s discovery is big.

Apache’s Liard holdings currently lie in a core covering 60 by 40 miles. The Lower Besa shale originates in a structurally stable, organic-rich marine environment with little clastic influx in quartz-filled deposits 400 to 1,000 feet thick inside a good boundary sequence.

“It has high pressure, it’s very brittle and it’s thick. Those are the three things that separate the Liard from most other basins,” notes Rob Spitzer , Apache Corp.’s vice president for Canadian exploration and a 30-year veteran in the western Canadian sedimentary basin (WCSB).

Work in the Liard commenced in 2007 following development in the Horn River, 60 miles east where Apache has been active since 2004. Apache’s geological team understood there were other regional plays besides the Horn River and opted to prospect in Liard while everyone was focused on Horn River.

The company drilled a vertical test in 2009, the D 28 B well, executed a single frac on a gas-saturated column of 708 feet and produced a 30-day IP of 4.6 MMfcd. The D 28 was followed in 2010 by a horizontal well, the D 34 K, with six frac stages, resulting in a 21 MMcfed 30-day IP.

This is the well that generated headlines two years later when Apache released results during its