Madalena tests oil in Argentina Vaca Muerta shale

July 19, 2011
Madalena Ventures Inc., Calgary, tested 40 b/d of 32° gravity oil from untreated Lower Cretaceous Vaca Muerta shale at the CAS X-1 well on the southern part of the 405 sq km Coiron Amargo block in Argentina’s Neuquen basin.

By OGJ editors
HOUSTON, July 19
-- Madalena Ventures Inc., Calgary, tested 40 b/d of 32° gravity oil from untreated Lower Cretaceous Vaca Muerta shale at the CAS X-1 well on the southern part of the 405 sq km Coiron Amargo block in Argentina’s Neuquen basin.

Further testing of the well, including a large hydraulic frac program, is expected to be completed in this year’s third quarter. If successful, Madalena could try to accelerate testing its other wells on the block using additional frac capacity being brought into the basin as well as proceed with preparations for a large, multiwell drilling program in 2011-12 specifically for Vaca Muerta shale oil.

Meanwhile, the CAN X-4 exploratory well on Coiron Amargo tested as much as 650 b/d of 39° gravity oil and 780 Mcfd of gas at 700-900 psi wellhead pressure on 4 to 8-mm chokes from the conventional Sierras Blancas formation. TD is 11,027 ft.

Both oil and gas shows were evident during the drilling of the Vaca Muerta and Sierras Blancas formations at CAN X-4. The Vaca Muerta shale interval is 456 ft thick. In the northern and southern parts of the block, Madalena has drilled into the Vaca Muerta formation five vertical wells, each of which appears similar on electric logs and have had indications of hydrocarbons.

YPF SA of Argentina earlier this year announced the delineation of a technically recoverable resource of as much as 150 million bbl of oil equivalent in the Vaca Muerta shale about 10 km west of the Coiron Amargo block. The shale appears to be gas prone along the broad western margin of the basin farther west of Coiron Amargo.

Dwayne Warkentin, Madalena president and chief executive officer, said, “The flow of oil from the Vaca Muerta shale in the CAS X-1 well prior to any fracture stimulation combined with the fracture stimulated results from the Vaca Muerta shale formation in the nearby Loma La Lata block provide the company with an excellent resource base in combination with the conventional Sierras Blancas oil play on the Coiron Amargo Block."

On the Cortadera Block, the CorS x-1 exploratory well is drilling at 9,760 ft targeting the Quintuco, Mulichinco, Vaca Muerta shale, and Tordillo formations. It is expected to reach TD of 14,100 ft in early August.

On the Curamhuele block, Madalena is finalizing plans to test several Lower Cretaceous Avile sands and the Lower Cretaceous Lower Troncoso formation encountered by the Yapai X-1001 drilled in June.

Based on electric logs, the well encountered 23 ft of potential gross hydrocarbon column in the Lower Troncoso at 4,640 ft measured depth, 4,394 ft true vertical depth. As programmed the well also encountered multiple stacked Avile formations at 6,800 ft MD, 6,530 ft TVD, to 10,620 ft MD, 10,360 ft TVD. Testing is to start in August.

Madalena holds 70% interest with Roch SA 20% in the Coiron Amargo and Curamhuele blocks 650 miles southwest of Buenos Aires and 90% interest in the Cortadera block 700 miles southwest of the capitol.