Northland Basin Bidding Round/Data Package
The Associate Minister of Energy, Hon Harry Duynhoven, today announced his intention to begin preparation for a
competitive Petroleum Exploration Permit Bidding Round over an area offshore Northland Basin.
"The Northland Basin is located immediately north of the productive Taranaki Basin. Initial interpretation, together
with the results of Wakanui-1 show that the Northland Basin is highly prospective" Mr Duynhoven said.
Planning for the 2004 bidding round was underway, although permit boundaries had yet to be confirmed, and relevant
consultation was still to be undertaken.
In preparation for the bidding round, the Ministry of Economic Development's Crown Minerals Group has joined forces with
the Institute of Geological and Nuclear Sciences (GNS) and UK-based seismic contractor Spectrum Energy & Information Technology to produce a substantial data-package on the basin's petroleum prospectivity.
"The partnership between Crown Minerals and Spectrum will provide explorers with state of the art reprocessed seismic
data" Mr Duynhoven said.
Spectrum has agreed to reprocess 9,100 kilometres of existing seismic from the offshore Northland Basin. Spectrum has
also entered into an agreement with GNS who will prepare an interpretation and hydrocarbon potential report, based on
the reprocessed seismic. This data will provide explorers with an understanding of the stratigraphic framework;
petroleum systems; play concepts; and trap types of the Northland Basin. The package will incorporate a revised
understanding of the basin's nearshore potential by utilising recently released data obtained from the deepwater
Wakanui-1 well, drilled off the continental shelf in 1999.
The data to be reprocessed are a 1,600 kilometre 1982 survey, originally acquired by Geco and the 7,500 kilometre 1995
survey acquired by Conoco and partners. Test lines are already showing significant enhancements in data quality and
imaging over the original processing. This is largely due to pre-stack time migration, advanced de-multiple techniques,
more detailed velocity analyses and improved post-stack migration.
Initial interpretation, from Wakanui-1 showed that the Wakanui structure is not buried by marine Cretaceous rocks as
previously believed. The presence of a Middle Jurassic coal measure succession strongly suggests the presence of a new
previously unsuspected petroleum system. Seismic data suggests that the depocentre to the east of the Wakanui structure
contains both Jurassic and Cretaceous source rocks and thermal modelling suggests that they are buried deep enough to be
generating and expelling hydrocarbons.
Reprocessing should be complete by end-January 2004, following which the interpretation report will be completed ahead
of the anticipated bid round.