By OGJ editors
HOUSTON, Feb. 25 -- An Anadarko Petroleum Corp. unit will operate a frontier exploratory well with Origin Energy Resources NZ Ltd. in the nonproducing Canterbury basin east of New Zealand’s South Island.
The companies will drill to an unstated depth to test the Cretaceous Kawau and Herbert formations on the twin-crest Carrack-Caravel prospect in 3,300 ft of water 40 miles east of Dunedin in the southern part of the basin. At Cretaceous level the prospect covers more than 390 sq km, compared with 160 sq km at Maui, New Zealand’s largest gas field.
Both formations contained hydrocarbons in the BP-Shell Todd Galleon-1 well that went to a total depth of 10,100 ft in 298 ft of water 18.6 miles northwest in 1985 (see map, OGJ, Feb. 3, 2003, p. 47).
Anadarko, which at its expense reprocessed Origin’s 2009 3D seismic data, will earn a 50% interest in PEP 38262 by paying the first $30 million of drilling costs. The firms will share costs 50-50 after that. PEP 38262 extends from south of Dunedin to south of Christchurch.
Drilling a well becomes a permit commitment after Aug. 21, and the companies likely will drill in 2011. They are seeking a suitable rig and wish to share mobilization costs with other operators.
Anadarko has an option to acquire for $100,000 a 50% interest in PEP 38264, which adjoins 38262 seaward, by Apr. 8.
Origin Energy said, “Seismic data over the structure is characterized by the presence of amplitude anomalies that conform to structure at the level of inferred Cretaceous reservoirs. More localized anomalous seismic responses are also observed in the overlying Tertiary sequence, which are interpretable as gas-charged reservoirs shallower in the section.”
The Galleon well flowed 10.6 MMcfd of gas and 2,240 b/d of condensate from Cretaceous sandstones at about 9,000 ft.
Origin Energy previously said Carrack-Caravel could hold a mean of 750 million bbl of recoverable oil or 2.7 tcf of gas and 500 million bbl of condensate in Herbert formation reservoirs. If Kawau sandstone reservoirs also trapped hydrocarbons, the recoverable volumes could more than double.