The Eagle Ford’s mystery is gone, but the play seems more alluring than ever.

Since 2009, the Eagle Ford has seen increases in drilling, well quality and production.

With more than 10,000 wells drilled in a dozen countries, the industry has concentrated 80% of all wells in seven economic counties. Gonzales, Karnes and DeWitt counties, Texas, come out best, on average, according to a report by Bob Brackett, senior analyst, Bernstein Research.

The core of the Eagle Ford is fully identified and Brackett’s calculations even say when it will begin to decline.

At a rate of 4,000 wells a year and assuming 60-acre spacing, the industry consumes 0.24 million acres a year. At that pace, the current sweet spot will be consumed in the next four to five years. The less economic prime area of the shale has closer to 18 years of inventory remaining.

However, the economics of wells are driven by peak rate, liquids content, and decline curve.

“Examining a single variable is misleading,” Brackett said.

Eagle Ford production should peak at about 4 million barrels of oil equivalent per day (boe/d) in 2021, Brackett said. That includes 2.4 million barrels per day (bbl/d) of liquids and 9.5 billion cubic feet equivalent per day (Bcfe/d) of wet gas.

Then, the wells the number of new wells drilled per year will begin declining.

Brackett ranked the best-in-class operators using metrics such as EUR at 20 years, total revenue at 20 years, and percent liquids.

EOG Resources (NYSE: EOG) is the clear winner, with nearly best-in-class results across the board. “The company’s only lackluster result is EUR, but EOG makes up for it with its high liquids content, driving higher revenue,” Brackett said.

Top Eagle Ford Operators

Chesapeake Energy’s (NYSE: CHK) flat decline curve drives up its EUR, total revenue, and discounted revenue at 20 years, landing the company in the No. 2 spot.

EOG is the top acreage holder, followed by Chesapeake.

Devon Energy (NYSE: DVN) follows with generally above-average results, particularly in those related to its relatively high peak rates.

“Its acquisition of GeoSouthern has proven effective,” Brackett said.

Going forward, the Eagle Ford’s inventory can be increased through further downspacing -- EOG believes it can conduct 40-acre spacing across its core, or on follow-on zones such as the Upper Eagle Ford as an independent zone, or Buda or other zones.

“We don't believe investors should ascribe 40-acre spacing to the entire play nor attribute significant value to other zones until such time as operators have demonstrated the commerciality,” Brackett said.

The Eagle Ford has become heavily concentrated in production and in wells.

Six operators -- EOG, CHK, Anadarko Petroleum Corp. (NYSE: APC), Marathon Oil (NYSE:MRO) ConocoPhillips (NYSE: COP) and BHP Billiton Ltd. (NYSE: BHP) -- are responsible for half the wells in the play, Brackett said.

About 50% of the wells have been drilled Dimmitt, La Salle and Karnes counties, Texas.

What is clear is that the best counties still have about the same average peak revenue per month and that well quality has evened out across the top counties.

And revenue has slowly equalized.

Ranking by peak revenue per month shows significant variation among counties in the second quarter of 2011. At the time, operators are holding acreage and drilling initial wells.

But by the first quarter of 2014, greater consistency has emerged in peak revenue per month. “In other words, we now have an Eagle Ford ‘factory,’” Brackett said.

Deal activity over the past five years has shown fewer signs of normalcy but prices appear to have peaked.

The price per proved boe peaked in 2013 at $22.15. The price per flowing barrel peaked in 2012 at $132.06.

In 2014, acreages prices have reached levels that approach 2012 highs.

“We believe that the 2012 high in price per acre was driven by speculation in the play whereas the current elevated prices reflect that fact that operators have now de-risked the play and are selling quality acreage at a premium,” Brackett said.