A new oily play is popping up in southern Arkansas and northern Louisiana. Actually, it’s an application of new-era, unconventional technology to a decades-old play, the Upper Jurassic Smackover.

While the Smackover occurs across a broad region, interest is particularly high these days in Lafayette, Columbia and Union counties, Arkansas, and Bossier, Webster and Claiborne parishes, Louisiana. This area falls in one of the interior Gulf Coast sedimentary basins, referred to as the North Louisiana Salt Basin or the Ark-La Basin. Its package of prospective sediments lies wedged between the Sabine and Monroe uplifts.

According to the Arkansas Geologic Survey, the Smackover formation takes its name from Smackover Field, in Union County, Arkansas. There, the formation is 700 feet thick. Its upper portion is composed of shallow-water carbonates, such as oolites, chalky limestones and corals. For many decades, explorers have targeted high-quality zones in the upper Smackover, and most existing Smackover fields in the region produce from porous oolite zones.

Interest has recently shifted to the lower portion of the formation, which lacks the reservoir qualities to produce at commercial rates with conventional technologies. The lower member is an extremely fine-grained carbonate mudstone, often called the Brown Dense. The lower and middle mudstone beds are excellent source rocks. They are quite thick, thermally mature and rich in kerogen, according to work done by Ernest Mancini, research professor at Texas A&M University. Much of the oil and gas produced in the North Louisiana Salt Basin has been generated in these mudstone beds.

“The upper Smackover play is fairly mature, but horizontal technology could ignite the lower Smackover play,” says a new report by analysts at Jefferies & Co. Inc., led by Subash Chandra. “Horizontal development of the Smackover—a zone just below the Haynesville—may be nearing proof of concept.”

Explorationists are closely watching a key well, Brammer Engineering’s #1-12 H Watson-Scott in Section 12, T18S-R22W, Columbia County, Arkansas, to see if it will provide that proof. The Shreveport-based contract operator drilled the horizontal test on the flank of Dorcheat Macedonia Field and has completed it as an oil well, according to IHS Inc. No flow rates were reported, but the 13,880-foot well is producing from an openhole Smackover lateral between 12,483-13,043 feet.

Brammer and its partner, Anderson Energy Co., also applied to the Arkansas Oil and Gas Commission to integrate Section 7-T18S-R22W for a horizontal Smackover test. The companies propose drilling that well to a vertical depth of 9,900 feet in Smackover, and then taking a lateral out 4,500 feet if the vertical wellbore confirms the presence of hydrocarbons.

A vibrant land play has been in progress in the region for several months, with field reports of positions of several hundred thousand acres being assembled. To add more spice, Core Lab’s Arkansas-Louisiana State Line Trend study analyzed 1,546 feet of conventional Smackover core pulled from 20 wells.

Now, Dallas-based J-W Operating Co. has an integration request in front of the Arkansas commission for Section 32-T19S-R17W in Union County. The company is proposing a horizontal well; vertical depth to Smackover is approximately 9,400 feet at its location. It has projected a lateral length of approximately 3,700 feet.

While there is not yet an announced success in the Smackover play, it is of strong interest due to its possible overlap onto leases originally acquired for the Haynesville shale, a dry-gas reservoir.

“We wouldn’t be surprised if operators more aggressively switch their attention to the liquids-rich Smackover,” says Chandra. The lower Smackover could be another example of a low-permeability/low-porosity zone that can be made commercial through horizontal drilling and multistage fracture stimulation.

Companies with existing positions in the potential lower Smackover area include Chesapeake Energy Corp., EOG Resources Inc., El Paso Corp., Forest Oil Corp., Petrohawk Energy Corp., Marathon Oil Corp., QEP Resources Inc., SM Energy Co., ExxonMobil Corp. and ConocoPhillips.