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Point McIntyre output still significant Complex of Alaska North Slope fields averaged 29,840 barrels per day over year ended March 31; operator BP submits work plans Wesley Loy For Petroleum News
The BP-operated Point McIntyre field is long past its prime, but it remains an important contributor to overall oil output from Alaska’s North Slope.
During the year ended March 31, Point McIntyre averaged 19,040 barrels per day of crude oil, condensate and natural gas liquids, BP says. The field delivered a total of 7 million barrels to the trans-Alaska pipeline.
The area known as Greater Point McIntyre ties in a number of related fields, including Lisburne, Niakuk, Raven, West Beach and North Prudhoe Bay.
These ancillary fields averaged a combined 10,800 barrels for the year, pushing total average production from the Greater Point McIntyre area to 29,840 barrels per day.
For the North Slope overall, production ran at close to 600,000 barrels per day.
BP holds a 26 percent ownership stake in the Greater Point McIntyre fields, with ConocoPhillips and ExxonMobil each holding a 36 percent share and Chevron a 2 percent share.
On June 28, BP submitted annual progress reports and development plans for the six fields to the Alaska Department of Natural Resources.
The Point McIntyre field Located seven miles north of Prudhoe Bay, the Point McIntyre field was discovered in 1988 with production starting in 1993.
Point McIntyre contained an estimated 880 million barrels of original oil in place. Production peaked in 1996 at 170,000 barrels per day, and the field has yielded more than 439 million barrels of crude so far.
Point McIntyre wells produce to the Lisburne Processing Center, as well as Gathering Center 1 in the BP-operated Prudhoe Bay field.
To boost production, BP employs enhanced oil recovery strategies.
“Point McIntyre is undergoing a tertiary recovery process involving alternating cycles of miscible gas injection and water injection that maximizes rate and recovery from the reservoir,” BP’s plan of development says. “Miscible gas injection will continue to be an integral part of the Point McIntyre reservoir management plan during 2012.”
Among accomplishments in the past year, BP says it drilled two wells — the P2-51A sidetrack from its parent well in the northwest area of the field, and a “grass root well,” the P2-39, on the field’s eastern side. The P2-39 replaced a well with a surface casing leak.
“Technical assessments are being undertaken to evaluate additional sidetrack opportunities,” the plan says. “Full-field model results may identify additional areas of bypassed oil that can be the target of infill drilling.”
On the maintenance front, BP took a 36-inch pipeline out of service due to concerns about external corrosion. The pipeline was used to send production to Gathering Center 1, a plant that separates oil, gas and water.
BP’s production forecast for Point McIntyre: “Long-term oil production is expected to continue to naturally decline from current rates due to increasing water cuts and gas-oil ratios.”
The complex Lisburne field The Lisburne field averaged 7,300 barrels a day of crude, condensate and NGLs for the year, and delivered 2.7 million barrels to the trans-Alaska pipeline.
BP describes Lisburne as “a complex, fractured carbonate reservoir that lies underneath and adjacent to the main Ivishak reservoir at Prudhoe Bay.”
The field was discovered in 1968 along with the giant Prudhoe Bay field and came onstream in 1986.
Lisburne contained an estimated 2.4 billion barrels of oil in place. Cumulative crude production to date is nearly 161 million barrels.
BP says Lisburne is “gas constrained,” with wells exhibiting a high ratio of produced gas to produced oil. This means oil production rates are “influenced by seasonal ambient temperature cycles and corresponding compressor efficiencies that in turn drive oil offtake rates.”
Some Lisburne wells respond positively to periodic shut-in, rather than producing continuously, BP says.
“Appropriate wells are rotated through a cycle of several days of production followed by days or weeks of shut-in,” the company says. When the wells are restarted, the gas-oil ratio generally is reduced, resulting in increased oil production.
BP injects seawater, and reinjects produced gas, to maintain reservoir pressure and boost oil production. A 9,300-foot water injection well was drilled in 2011.
To support the Wahoo and Alapah reservoirs, BP is planning to convert three production wells to water injection. Long lead items required for these waterflood conversions have been ordered, the company says.
In coming years, BP says it will evaluate potential Lisburne drilling targets, including more injection wells.
Niakuk and Raven satellites Crude, condensate and NGL production from the Niakuk satellite field averaged 3,100 barrels per day in the year ended March 31. A total of 1.1 million barrels was delivered to the trans-Alaska pipeline.
Niakuk is located offshore, but produces through the onshore Lisburne facility. Original oil in place was about 400 million barrels.
BP says it’s not planning any new projects in Niakuk. But the field might see more development drilling in the future.
“Niakuk development well targets are continually being evaluated and technical work to assess potential infill and peripheral drilling locations continued during the report period,” the annual report and development plan says. “Technical assessments are being undertaken to evaluate sidetrack opportunities.”
The Raven satellite averaged 400 barrels of production a day, and delivered 150,000 barrels to the trans-Alaska pipeline. Most Raven production comes from a single well, supported by a water injection well. Because the Raven producer, NK-38A, is still performing well, BP says it has no plans to sidetrack it.
West Beach, North Prudhoe Bay Two other Greater Point McIntyre satellite fields, West Beach and North Prudhoe Bay, are not in production.
Production at West Beach was suspended in 2001 due to increasing gas-oil ratios and declining reservoir production. Delineated with 11 penetrations including seven wells and four sidetracks, the field has produced a total of 3.37 million barrels of crude, with 92 percent coming from the original WB-04 well.
“Since the suspension of production in 2001, fieldwide reservoir pressure has increased,” the West Beach annual report says.
The WB-04 well had 165 feet of perforations added in 2008, and it was tested that year and again in 2009. In 2009, the well produced 5,588 barrels of oil and 52,723 barrels of water during the 66 days it was online. Another well, the WB-05B, produced 4,409 barrels of oil and 6,647 barrels of water over 23 days.
“Results of the 2009 production testing will be used, in conjunction with a revised geologic model, to evaluate the West Beach participating area’s remaining reservoir potential and options for future development,” BP’s development plan says.
Production through West Beach’s 6-inch and 12-inch production pipelines won’t be restarted until the lines receive an internal integrity inspection using a “smart pig” device.
“Current plans are to pig these lines in 2013,” the plan says.
The lone production well in the North Prudhoe Bay field was shut-in during February of 2000 due to safety concerns arising from proppant production from a fracture stimulation of the Sag River formation. Proppants are sand or engineered particles mixed with fracturing fluid to hold fractures open after a hydraulic fracturing treatment.
A 2005 well treatment failed to stop the proppant flowback.
BP has determined the well, WB-03, is “not safe to flow in its present condition.” In the coming year, the company says it might begin an evaluation of the remaining reservoir potential and development options at North Prudhoe Bay, which has produced a total of 2.1 million barrels of crude and condensate to date.
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