THE jack-up Ensco Rig 107 looks set to return to Singapore after two years in New Zealand waters unless explorers utilise the vessel once it finishes the offshore Taranaki Manaia-1 well later this year.
Ensco 107 jack-up drilling rig
The rig, commissioned and launched as a newbuild in Singapore in early 2006, arrived in New Zealand waters in October 2007, primarily for the $NZ1.2 billion offshore Taranaki Kupe gas-condensate project operated by Origin Energy.
Afterwards the rig drilled the non-commercial Momoho-1 near-field appraisal well for the Kupe partners before bad weather hampered its move to begin the development drilling campaign for the billion-dollar Maari oil project operated by Austrian giant OMV further south.
The rig is finishing the last of three water injection wells at the Maari field before drilling the final two of five oil production wells. It will then drill the Manaia appraisal well as an extended reach horizontal well from the Maari platform.
It is known that OMV has eight options on the rig after Maari and that Origin Energy has two options.
However, Origin’s geoscience and exploration new ventures manager Rob Willink has confirmed to PetroleumNews.net that Origin will not be using the rig.
Last July, Willink indicated a further appraisal well could be drilled if a review of Momoho – in association with two other nearby hydrocarbon accumulations discovered by the Kupe South-4 (gas) and Kupe South-5 (oil) wells about 20 years ago – proved positive.
Momoho-1 encountered a 25m-thick gas-condensate pool in the Palaeocene-aged Farewell Formation – the primary reservoir at Kupe.
However, Willink yesterday told PNN that while work to evaluate the remaining exploration potential within the Kupe mining licence was continuing, “in the light of the Momoho results, in all probability, any prospects we may mature to drillable status are likely to be gas prone, and comparatively small”.
“As such, if they were drilled and successful, they would not need to be tied into the Kupe platform until the latter stages of field life. Hence there is no urgency to drill them now.
And we do not intend to exercise our two remaining options,” Willink said.
Industry commentators say it is likely OMV will also choose not to exercise any of its options as OMV does not have any well commitments in either of its other offshore Taranaki licences – PEPs 38485 and 381200 – until late 2011 or 2012.
However, the company is urging other explorers to utilise the vessel before it leaves, saving the high mobilisation-demobilisation costs associated with bringing another jack-up to New Zealand waters.
Other players that could use the rig late this year or early next include Australian Worldwide Exploration, Singapore’s STP Energy, Energy Corporation of America, and integrated energy player Genesis Energy.
It is known that AWE has a commitment to drill a wildcat in its 100%-owned PEP 38534, near D'Urville Island at the top of the South Island, by next April, though company corporate development manager Garry Marsden has declined to comment on the possibility of AWE using the Ensco 107.
STP Energy is investigating the feasibility of committing to the second of its two wells, the Kahu-1 wildcat, it planned last year in its offshore Taranaki licence PEP 38479.
The company only drilled the non-commercial Awakino South-1 well before the jack-up Ensco Rig 56 – which had earlier spent more than two years drilling five development wells in the near-shore Pohokura gas field – left for Singapore last December.
Energy Corporation of America, which operates in New Zealand as Westech Energy, has applied for a second five-year term for its offshore Taranaki licence PEP 38491, primarily so it can drill the Albacore-1 wildcat late this year or early next, perhaps with the Ensco 107.
Finally, Genesis could also utilise the rig to drill a well into the onshore-offshore Mangatoa prospect, targeting the Taniwha formation, in its licence PEP 381204.
The Maari partners are operator Austrian firm OMV (69%), Todd Energy (16%), Horizon Oil (10%) and Cue Energy Resources (5%).
The Kupe partners are operator Origin Energy (50%), Genesis Energy (31%), New Zealand Oil & Gas (15%), and Mitsui E&P NZ (4%).