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Duncan reveals little about test well Says first North Slope shale oil well proceeding to plan but provides few clues about progress in coring or testing of source rocks By Alan Bailey Petroleum News
Anyone attending K&L Gates’ Alaska Shale Conference on July 31 anticipating new information about Great Bear’s first proof of concept shale oil test well on Alaska’s North Slope would have come away disappointed. Ed Duncan, the president of Great Bear, overviewed the company’s Alaska shale-oil program but provided few clues about progress in drilling the Alcor No. 1 well, an 11,000-foot, near-vertical well that was planned to spud in June. Great Bear plans to take cores from the three major North Slope source rocks, from deepest to shallowest: the Shublik, lower Kingak, and an assemblage called the Hue shale and HRZ or GRZ.
The idea is to send core samples to laboratories for testing, to determine the production characteristics of the rocks. The company is pioneering the possibility of oil production on the North Slope using the hydraulic fracturing techniques in source rocks that have proved so successful elsewhere in North America.
First target On July 9 Great Bear Vice President Pat Galvin told Petroleum News that the Alcor 1 well had almost reached the HRZ and that coring of that rock unit should be done within the next few days. Since then the company has remained silent on drilling progress.
“The results to date are within our expected outcome,” was all that Duncan would offer during his conference speech in terms of progress with Alcor 1. Asked later by Petroleum News whether any coring had been done, Duncan said, “Just look at the smile on my face,” before turning away.
And, when asked during the Q&A session after his talk whether Alcor 1 had yet drilled past the HRZ, Duncan said that the company has followed the drilling program specified in the company’s plan of operations, as described in various company presentations.
In response to a question about near-term expectations Duncan said that Great Bear could be producing hydrocarbons by the end of the year.
“We expect to be testing and producing and … selling produced hydrocarbons potentially by the end of the year, and certainly early next year,” Duncan said. If the drilling program proves successful and development moves ahead at the pace Great Bear would like to see, it would be reasonable to expect oil shale production of at least 100,000 barrels per day within five years, he said.
Seismic section Duncan’s comment about the Alcor 1 well came in the context of showing conference attendees a seismic section, pulled from a 3-D seismic survey that Great Bear has conducted in its lease area. The seismic section, running along the line of six test wells that the company plans to drill adjacent the Dalton Highway, beautifully depicted the subsurface traces of the HRZ and Shublik source rock zones in an area that the U.S. Geological Survey views as having a high potential for oil-bearing source rock. But the section, although showing the well locations, did not depict the actual drilling trajectory of the Alcor well.
Duncan said that the seismic data would enable detailed geologic information gleaned from the Alcor well to be extrapolated rapidly to the other Great Bear drilling sites.
In his July 9 statement Galvin said that after completing the vertical well at the Alcor site, the drilling rig would move south to drill a vertical well at the Merak drilling site. Alcor is the most northerly of Great Bear’s drilling sites, and Merak is the next site to the south.
Seismic survey 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, Galvin said.
“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,” he 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.
Lidar survey During his talk at the Alaska Shale Conference Duncan said that Great Bear is just a few days away from initiating a very high resolution Lidar survey of a 200-square-mile swath of territory around its drilling sites. Lidar uses light pulses from an airborne laser system to very precisely map surface topography and provide detailed information about some surface features.
“This will provide a topographic and mapping data set that does not exist in northern Alaska at this time,” Duncan said, adding that, weather permitting, the technology being used can achieve topographic resolutions of a few centimeters.
This survey, backed up by ground surveys, will provide vegetation maps and valuable information about water depths and water volumes in lakes, enabling insights into whether lakes are likely to be fish bearing, Duncan said.
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