Grant Geophysical started the onsore-offshore survey, in licence PEP 38729, last week and looked likely to finish the 2D survey of the prospects next week, NZOG geophysics manager Stefan Kleffmann told PetroleumNews.net today.

He said the latest survey should provide a critical link between previously acquired onshore and offshore lines to improve the structural definition of the Felix and Opito-Updip prospects.

Earlier this year, the Institute of Geological and Nuclear Sciences conducted a refraction seismic survey over Felix and Opito-Updip to understand more clearly the prospects in the remote and rugged coastal strip in northern Taranaki. At the time, NZOG said a lack of accurate velocity mapping over the area had hindered earlier exploration in the area.

The survey shots – of up to seven 8km-long onshore-offshore lines – were being recorded on a receiver spread that spanned the gap between existing onshore and offshore seismic lines.

Processing and interpretation of the latest data was scheduled to be finished by December and a decision made early next year regarding whether to drill a second well.

“Prospectivity in the Eocene-aged Kapuni Group is good and we believe this area is one of the few lucrative spots left in the Taranaki Basin. However, we will have to wait to find out what the latest data says before deciding to drill or not,” Kleffmann said.

The acquisition geometry was tailored to undershoot the basement overthrust, in order to better illuminate the Eocene-aged Kapuni Group sandstone reservoirs that were intensely deformed in the Oligocene-Early Miocene convergence of the Pacific and Australian tectonic plates.

Eocene-aged Kapuni C sands are widespread over offshore and onshore Taranaki and are the main producing reservoir at the offshore Pohokura and Maui fields in the south of the region.

NZOG has previously said the Felix and Opito-Updip prospects could hold up to about 70 million barrels of oil, but general manager Gordon Ward today told PNN that figure was speculative.

PEP 38729 partners are: NZOG (operator and 75%) and Origin Energy (25%).