Minority partner New Zealand Oil & Gas this morning reported that Momoho-1 had discovered the small gas-condensate pool within thin, good-quality sandstones of the Palaeocene-aged Farewell Formation - the primary reservoir of the nearby Kupe field.
NZOG said that wireline logging, and pressure and fluid sampling, had confirmed last week's reported good gas indications recorded from the top of the Farewell Formation at 2896m measured depth from rotary table (MDRT).
Preliminary interpretation indicated the well had intersected a gross gas-condensate column over the interval 2896m-2921m MDRT.
NZOG added that the accumulation was located on the crest of the Momoho anticline, on the southwestern side of a central fault.
The potential remained for hydrocarbons to be trapped within a large closure on the northeastern, downthrown side of this fault, given the presence of gas-condensate at Momoho-1, as well as gas nearby at the Kupe South-4 well (2.5km to the northeast) and oil at the Kupe South-5 well (1.2 km to the south), which were both drilled about 20 years ago during the discovery of Kupe.
NZOG said evaluation of this portion of the Momoho anticline would be considered at a future date by the joint venture once the full implications of Momoho-1 had been considered.
Further studies would be undertaken to determine whether it might be possible to contemplate a development combining these existing and potential hydrocarbon accumulations.
Momoho-1 is 6km southeast of the Kupe production facilities in the central field area of the Kupe mining permit PML 38146 off the coast of South Taranaki.
Origin and its partners will plug and abandon Momoho-1, which reached its total depth of 3145m MDRT on Monday this week, once they have completed their current evaluation program.
Wellington-headquartered NZOG has previously said it expects the Momoho prospect to contain estimated total recoverable reserves of about 200 billion cubic feet equivalent (Bcfe), combining gas, oil and LPG estimates determined at the P50 level.
The potential to tie back future near-field discoveries has already been incorporated into the Kupe development infrastructure.
First gas from the $NZ1.1 billion ($A0.87 billion) Kupe development is expected in mid 2009.
Kupe's estimated 2P reserves are 254 petajoules of gas, 14.7 million barrels of condensate and 1.1 million tonnes of LPG.
Today NZOG also said the Kupe joint venture expected to release the jack-up Ensco Rig 107 early next week, subject to a suitable weather window.
The rig will then move further south to start drilling the scheduled five oil development wells, plus three water injection wells, for the $US508 million ($A521 million) Maari development project headed by operator Austrian firm OMV.
The Kupe partners are operator Origin Energy (50%), Genesis Energy (31%), New Zealand Oil & Gas (15%), and Mitsui E&P NZ (4%).
