Transworld To Carry Out Seismic Survey on Tui Prospect

A 3D seismic survey is planned by Transworld after Tui-1 oil discovery offshore Taranaki. The discovery of oil has been made in the Kapuni F sands of the Tui-1 well in offshore Taranaki permit PEP 38460. The well, about 20 km northwest of the Maui field, is operated by New Zealand Overseas Petroleum Ltd (NZOP), a subsidiary of the Bermuda-registered Transworld Oil group.

Former operator New Zealand Oil & Gas Ltd, said the Tui-1 well encountered a gross oil column of 10 m within the Kapuni F sands, of which 100% was net oil pay in excellent quality reservoir rocks.

The well was drilled by the Ocean Bounty semisub, its fourth and final well in its New Zealand summer campaign.

NZOG exploration manager Eric Matthews said that the partners now hoped to move as early as March to acquire 3D seismic over the Tui prospect with a view to further delineating the prospect and possibly drilling some appraisal wells later this year.

Dr. Matthews said Tui-1 on its own looked to be a marginal discovery, though if the partners proved up further reserves by subsequent successful appraisal drilling then the field should prove commercial.

He said the implications of oil charge in the Kapuni F sands rather than gas had upgraded the other prospects within the permit. Prospects such as Hector, Tahuroa and Pukeko could prove to be oil plays.

The primary objective of the well, the Kapuni D Sands, was encountered slightly high to prediction and was associated with only minor oil shows and low levels of cuttings gas. Subsequent wireline logging confirmed that no producible hydrocarbons were present in this interval. The other well target, in the Moki Formation, also proved dry.

When the Kapuni F sands were encountered at 3655 m, elevated cuttings-gas and hydrocarbon fluorescence were observed over the uppermost 20 m of the sand. These observations were interpreted to indicate gas but subsequent evaluation of the wireline data, including MDT fluid sampling, indicated the 10 m oil column.

Tui-1 reached its total depth of 3903 m in early February. The well is to be plugged and abandoned as scheduled.

Late last year New Zealand Overseas Petroleum took a 45% stake in PEP 38460, leaving NZOG, through Stewart Petroleum Company Ltd, with a 20% interest, NZOG associate Pan Pacific Petroleum, through WM Petroleum Ltd, a 15% interest and AWE New Zealand Pty Ltd 20%.