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Savant announces restart at Badami Oil has started flowing again from the field following the drilling of a horizontal sidetrack and an exploration well last winter Alan Bailey Petroleum News
The Badami oil field, the most easterly of the developed fields on Alaska’s North Slope, went back into production on Nov. 5, Greg Vigil, an executive of Savant Resources, told Petroleum News. Savant and Arctic Slope Regional Corp. have been working with field operator BP since 2008 to bring the troubled field back on line, following a 2007 field shutdown intended to allow the field’s reservoir to recharge with oil.
Earlier this year, Savant drilled a new exploration well, the B1-38, in the Badami unit, having also drilled a new horizontal sidetrack well in the Badami reservoir to test the use of horizontal drilling techniques to tease a higher oil flow rate from the field. The company planned to bring six wells on line in the startup, including production from an oil bearing horizon in the exploration well and production from the horizontal well.
The B1-38 well tested a prospect called Red Wolf involving the Kekiktuk formation, the formation that contains the oil reservoir for the Endicott field some miles to the west. Savant has remained tight lipped about its results from the Kekiktuk but has said that it found oil in a higher-level secondary target in the Cretaceous Killian sands. Oil production from the B1-38 well would come from that Killian sands oil pool, Vigil said in August.
The reservoir for the 120 million Badami field is in younger and shallower rocks in what geologists call the Brookian sequence.
Troubled history The field has had a troubled history since it first went into production in 1998, with an anticipated 30,000-barrel per day startup production rate actually coming in closer to 18,000 bpd and then dropping to less than 3,000 bpd by early 1999. Faced with unsustainable winter oil flows down the Badami pipeline, BP shut the field in between February and May 1999. Then after unsuccessful attempts to improve production through the use of gas injection and the drilling of lateral wells from the field’s original well bores, BP placed the field in warm shutdown between 2003 and 2005.
In 2007 BP shut the field in again, and the field remained dormant until this month’s restart.
The production problems at Badami result from the highly compartmentalized field reservoir, formed from sands that fill a complex network of ancient submarine channels, interlayered with impervious shales. Initially, oil tends to flow at a good rate into an individual production well as individual sand channels are drained, but production then drops off as barriers between the channels inhibit the drained sand from recharging, a problem compounded by the somewhat viscous character of some Badami oil.
In 2006 BP proposed the use of horizontal wells to improve production rates by threading wells through the reservoir sands and thus increasing the reservoir volume exposed to each well bore. Savant and ASRC formed a deal with BP in 2008 to drill two wells and try the horizontal well production concept.
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