Great Bear Petroleum’s first North Slope test well, the Alcor No. 1, has almost reached the HRZ oil source rock, the first of the source rocks from which the company wants to obtain core samples, Pat Galvin, Great Bear’s vice president of external affairs, told Petroleum News July 9.
“We’re in progress moving towards our first zone for coring,” Galvin said, adding that the coring should be done within the next few days.
The near vertical well will eventually penetrate and sample all three of the major North Slope source rocks — the HRZ/GRZ, the Kingak and the Shublik — before bottoming out at a depth of over 11,000 feet. Great Bear will send samples from the cores to laboratories for testing, to determine the production characteristics of the rocks.
Great Bear is pioneering the possibility of oil production on the North Slope using the fracking techniques in source rocks that have proved so successful elsewhere in North America.
Merak well
After completing the vertical well at the Alcor site, the drilling rig will move south to drill a vertical well at the Merak drilling site, the next of a series of drilling sites that Great Bear has staked out close to the North Slope haul road. The company is drilling in an area to the south of the producing North Slope oil fields, an area where the source rocks are thought particularly likely to contain producible oil.
Producing oil will involve fracturing horizontal wells drilled laterally through the target source rocks. And so after taking core samples from the vertical Merak well, Great Bear plans to proceed to the next stage of its testing program by drilling horizontal lateral wells from the vertical well bores.
“The plan is to immediately transition into a lateral well at the Merak site and then we’ll go back … and do a lateral well at the Alcor site,” Galvin said.
Great Bear wants to complete the two vertical wells and two horizontal wells, and to drill another vertical well at a third site, the Mizar site, before the end of 2012, he said.
“We’re making good progress,” Galvin said.
—Alan Bailey
