Australia’s Samson Oil & Gas Ltd. completed an initial multistage acid stimulation on the Maris 1-16 H well on June 24, the company said June 28. Maris 1-16H is a horizontal openhole completion in the Ratcliffe member of the Mississippian Madison Formation, which is predominantly a limestone reservoir in Montana and North Dakota.

The well has produced 177,000 barrels (bbl) of oil after being initially drilled in 2004. The well was acquired as part of a package of wells in an acquisition that closed on April 1. Samson became operator of this well on June 5.

The stimulation job placed 4,600 bbl of HCl acid, other water-based fluids, 4,200 bbl of diversion agent, spacers and pads in 19 stages across five zones. Samson said that it will take about 14 days to determine how effective the acid stimulation was.

Samson has a three-pronged approach to increase the production from the Foreman Butte project by working over shut-in wells with mechanical problems; working over shut-in horizontal wells with advanced stimulation potential, and by proving undeveloped drilling.

Working over shut-in wells is almost complete, and will be completed soon, with 19 wells being brought back onto production over the last six weeks. Four workover rigs were recently active in Montana and North Dakota. These workovers increased the company’s production to 1,322 bbl/d currently, from 834 bbl/d at the end of April.

Working over shut-in horizontal wells with advanced stimulation potential has partially been met through the Maris 1-16H stimulation. An additional 15 wells might be stimulated, Samson said.

The proved undeveloped drilling program is expected to begin in the first quarter of 2017.