The Parker Drilling Rig 246 spudded Mangahewa-3 late last week and could take a month or longer to reach the Mangahewa sands within the Eocene-aged Kapuni Formation.
If the Mangahewa field does prove to be an extension of Pohokura – which is by no means certain – the appraisal drilling campaign could possibly add 250 billion cubic feet (Bcf) to the field’s remaining gas reserves, which Crown Minerals estimates are now only about 32Bcf, according to Todd managing director Richard Tweedie.
“We already have another two further appraisal wells planned for Mangahewa, but will wait until we get the results from Mangahewa-3 and have analysed those before committing ourselves to the two additional wells,” Tweedie told PetroleumNews.net from Wellington.
The Mangahewa petroleum mining licence PMP 38150 currently produces from the sole Mangahewa-2 well, which draws from only one of several Mangahewa sands intervals.
Mangahewa-3 is the first well in the field since Todd took over the field from former owner-operator Fletcher Challenge Energy (FCE) early this decade.
FCE had planned a separate production station for Mangahewa gas when it thought the often-tight Mangahewa sands extended north and perhaps even offshore.
But it dumped those plans after the then Pohokura partners FCE, Shell, Preussag Energie and Todd drilled the deviated Pohokura South-1B well in 2001, with former FCE chief operating officer (and later Shell NZ chairman) Lloyd Taylor saying the Pohokura structure probably only just “nicked” onshore and did not continue southward.
Gas and liquids are now separated at the Mangahewa-2 wellsite, with liquids processed at the nearby McKee production station.
Private company Greymouth Petroleum’s announcement earlier this year – that its Turangi-1 well was commercial – re-ignited comment from some industry observers about the possible linkage of Pohokura, Turangi and Mangahewa.
Earlier this month, the Parker 246 rig plugged and abandoned Todd’s Te Kiri-2 well to the southwest of Mangahewa.
“We did have some hydrocarbon shows at Te Kiri-2 but the reservoir was tight and therefore not commercial,” Tweedie said.
“It is possible we could drill another well in that area and are looking at that right now. We have not yet finished with Te Kiri.”
Todd drilled Te Kiri-2 as 100% owner of licence PEP 38749 after last year undertaking the third-largest 3D onshore Taranaki seismic survey, covering about 90 square kilometres, over a large faulted anticlinal closure.
That seismic let Todd accurately map the structural extent of the Te Kiri anticline it believed Petrocorp missed 20 years ago with Te Kiri-1, a well that encountered multiple hydrocarbon shows during drilling.
