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Great Bear determining its next steps Company has completed first two vertical test wells and is evaluating drilling results before moving ahead with more drilling Alan Bailey Petroleum News
Great Bear Petroleum has now completed both of its initial vertical test wells, the Alcor No. 1 and the Merak No. 1, and is in the process of determining the next steps in its shale oil project on Alaska’s North Slope, Patrick Galvin, Great Bear’s vice president of external affairs and deputy general counsel, told Petroleum News in a Nov. 2 email.
“Great Bear is currently conducting complex technical analysis on the well data and whole cores to evaluate the results,” Galvin said. The company has acquired a large amount of core and other well data, he said.
Found oil In September Ed Duncan, Great Bear’s president and CEO, told the Alaska Oil and Gas Congress that his company had found oil as anticipated in source rocks encountered by the Alcor well and that the thicknesses of the source rocks penetrated by that well had exceeded expectations. The well penetrated all three of the North Slope’s major source rock intervals: the Shublik, the lower Kingak and the GRZ/HRZ.
Great Bear has acquired state leases across a fairway of land in a region south of the producing North Slope oil fields, in an area where geologists think it likely that the source rocks have in the past generated oil. The company wants to determine whether it is possible to viably produce oil directly from any of the source rocks, in a similar manner to oil production in shale oil plays such as the Eagle Ford and Bakken in the Lower 48 states.
Great Bear has staked out a series of six test wells alongside the North South Haul Road, to the south of Deadhorse. The Alcor No. 1 and Merak No. 1 are the two most northerly wells in this series.
The initial purpose of the test wells is to obtain rock core and well data, to determine whether shale oil production seems possible. But, assuming that this initial testing pans out, determining the technical and economic viability of production will then entail drilling and hydraulically fracturing horizontal wells through target source rocks, to test the oil production characteristics of the rocks.
In July, while the drilling of Alcor No. 1 was in progress, Galvin told Petroleum News that Great Bear hoped to drill a horizontal lateral well out from the vertical Merak No. 1 for an initial production test, after the drilling of the vertical well had been completed. The company then expected to move back to the Alcor 1 well to drill a horizontal lateral there, before heading south to drill a third vertical well, the Mizar well by the end of the year.
Extended testing Since then, apparently buoyed by the initial drilling results, Great Bear has applied to Alaska’s Division of Oil and Gas for permission to conduct extended production tests using its initial horizontal wells, once these wells have been drilled. The company’s approved plan of operations assumes just five to seven days of testing but the company wants to extend the test durations to 180 days. This extended testing would eliminate the need for a pilot test pad for production testing, thus potentially enabling a decision in mid-2013 on whether to move to a full-scale shale-oil development, Duncan told the Oil and Gas Congress. Great Bear had anticipated making that decision in 2014.
One complication is an unanticipated problem in the Alcor No. 1 well. Apparently a glitch that occurred during the drilling of that well resulted in the installation of well casing that is unsuitable for drilling the horizontal sidetrack that is necessary for production testing. Great Bear has requested approval from the Division of Oil and Gas for a change to Great Bear’s plans, to allow the drilling of a second Alcor well, so that the horizontal well can be drilled.
But at this point Great Bear has not said what its next drilling operation will be. Based on the anticipated timing laid out in the company’s plan of operations, the drilling program would appear to have slipped a little behind schedule. And with access to a single drilling rig, the company must presumably decide on one of the two or three drilling options that are possible for the next step in the company’s program.
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