GMX alterations may improve Bakken completions

GMX Resources Inc., Oklahoma City, is adjusting its operating practices in an effort to improve results of Bakken completions in the Williston basin.

Changes being implemented include using oil base mud during the entire drilling operation, switching to plug and perf completions versus sliding sleeve, using more proppant and using ceramic proppant in the mix. The company also needs to reduce pump downtime by installing more reliable diesel electric generators on the pumps in areas without electric service, which is most of its core acreage.

The company reiterated that from this point its drilling will target the Middle Bakken in McKenzie and Billings counties, ND, where completions generally yield 90% oil.

GMX has an 89% working interest in its eighth operated well, Basaraba 34-35-1H, its first Middle Bakken well in Billings County. The well, which the company said has the potential to be its best, had a peak rate of 1,673 b/d of oil equivalent with 1,000 psi flowing casing pressure on a 48/64-in. choke.

Basaraba was successfully fracture stimulated using a 39-stage plug and perf completion. It was fracture stimulated with 25% more proppant, 4 million lb, which was 44% white sand and 56% ceramic proppant.

GMX used the plug and perf method for the first time at Basaraba, which included cleaning out the lateral. The coiled tubing unit was released on Sept. 30 after milling out 33 plugs and reaching a total length of 19,000 ft. Basaraba has 5-day cumulative production of 4,375 boe.

At the company’s seventh operated well, Fairfield State 21-16-1H, in Billings County, the sliding sleeve completion of the Three Forks screened out after the first four stages. GMX was able to complete less than 30% of the rest of the lateral as a modified plug and perf design. The well’s peak was 177 boe/d. The Middle Bakken looked good in the pilot hole and will be the target of future development.

Akovenko 24-34-2H in McKenzie County, the company’s first well drilled with oil base mud, went to 20,997 ft measured depth including a 9,341 ft lateral in less than 30 days for $4 million. A Middle Bakken plug and perf completion is to begin in late October 2012. This ninth operated well will be the first plug and perf completion in McKenzie County in the Middle Bakken and the first completion in a lateral drilled with oil base mud.

The oil base mud should have caused little damage to the rock's natural permeability and porosity, GMX said. The company has a 92% working interest in the well. The Akovenko 24-34-2H will be the first well drilled with oil based mud and using a plug and perf completion methodology, completion recipe to be determined. The south offset Akovenko 24-34-1H was drilled with water base mud, completed 30 stages with sliding sleeves, and should provide a good contrast to the Akovenko 24-34-2H.

GMX has spudded its 10th operated well, the Lange 44-31-2H, in McKenzie County, with an 89% working interest. The well targets the Middle Bakken with a proposed measured depth of 21,261 ft including a 9,587-ft lateral. Lange will be GMX’s second well drilled with oil base mud and completed with plug and perf in McKenzie county. It will be drilled parallel to the Lange 11-30-1H and provide another comparison similar to the Akovenko wells.

GMX has elected to participate with 2% working interest in drilling the Marsh 41-16PH in Stark County.