Appraisal wells may shrink Juha potential reserves

April 3, 2007
Initial results of the Oil Search Ltd.-operated Juha-5 appraisal well in the highlands of Papua New Guinea indicate a small increase in the gas column in this sector of the field.

Rick Wilkinson
OGJ Correspondent

MELBOURNE, Apr. 3 -- Initial results of the Oil Search Ltd.-operated Juha-5 appraisal well in the highlands of Papua New Guinea indicate a small increase in the gas column in this sector of the field.

However potential reserves of Greater Juha gas-condensate field have been reduced to 2 tcf of gas after the Toro Sandstone reservoir was shown to be water-bearing.

Field reserves are expected to be better understood after the drilling of Juha-4, which will immediately follow Juha-5.

Oil Search, Sydney, says the gas column—from the highest known gas at Juha-1 to the gas-water contact defined by pressure readings in Juha-5—is now put at about 250 m.

Juha, originally found in the 1980s, is a remote field that needs large reserves to justify development. Oil Search and its partners ExxonMobil and Merlin Petroleum Co. Inc., Stamford, Conn., were hoping for reserves of up to 4 tcf of gas and 150 million bbl of condensate. The group may have to reconsider its options if the gas figure is confirmed as closer to 2 tcf.

Oil Search sees Juha as a potential source for a proposed liquids recycling project with a capital cost of about $850 million (Aus.) for the production of 450,000 b/d of condensate. This later could be linked to an LNG project.

Oil Search is operator of the Juha wells, while ExxonMobil is operator of the surrounding PRL2 retention license. Juha field interests are ExxonMobil 56%, Oil Search 31.5%, and Merlin 12.5%.