There have been 35 permits for oil and gas exploration around the country since National gained power and the GSB south of Dunedin has attracted a lot of seismic hydrographic interest, plus some test drilling in the Canterbury Basin.
The inaugural Advantage New Zealand Petroleum Summit attracted about 500 delegates and a small number of protesters to Auckland's SkyCity conference centre yesterday.
Mr Bridges announced four offshore blocks, combined in the Great South Basin-Canterbury, Pegasus (off Wairarapa), Taranaki and Northland-Reinga basins.
''We have 17 others [basins] that are underexplored, which I want to see changed,'' Mr Bridges said.
He even went so far as to say Taranaki remained ''relatively unexplored'', while acknowledging it had been the cornerstone of the country's oil and gas production.
The GSB-Canterbury basins block offer, which closes for tender in six months, with an announcement likely by December, covers the second-largest area of the four basins, at 141,000sq km.
Northland Reinga is 186,000sq km, Taranaki 53,000sq km and Pegasus 44,000sq km.
The onshore blocks are in Taranaki, and two are on the West Coast. The total on and offshore area is 429,298sq km.
Following the announcement, Mr Bridges said in an interview that while the oil price decline was an issue for the industry, he was confident that the price would eventually recover, highlighting the large exploration companies were able to take out 15-year permits, with relatively inexpensive exploration costs during the first six years.
He described the GSB-Canterbury basins as the ''holy grail'' within New Zealand's overall image of being a ''frontier play'' for exploration in general.
''There is clearer acceptance of a system there,'' Mr Bridges said of oil and gas exploration in the two southern basins, going back to the 1970s.
Canterbury Basin, just offshore from Oamaru, continually attracts explorers, despite no commercially viable condensate (light oil) or gas deposits having been found.
Talking about the presence of protesters, kept outside the conference centre by increased and ponderous security arrangements, Mr Bridges reiterated that a change to renewable energy had to be ''transitioned'' and non-renewable could not ''have the tap turned off overnight''.
''Significant gas finds in New Zealand could displace coal,'' he noted.
Petroleum Exploration and Production Association (Pepanz) chief executive, Cameron Madgwick, welcomed the latest block offer, highlighting economic benefits to the country.
Taranaki's per capita gross domestic product was $74,341 and average weekly earnings $918, the highest of any province beyond main centres.
He said the offer was the start of a long process to establish whether oil and gas were there in commercial quantities.
''Production from a successful discovery will be at least seven years away,'' he said.
While Anadarko had been unsuccessful in drilling north of Dunedin, it had since taken time to recently carry out more seaborne 3-D hydrographic testing in the area. Its decision on whether to drill again could be up to two years away.
Mr Madgwick said it was important communities around the country were given the facts about the oil and gas sector, from the beginning of the permitting process, exploration and on to production.
''Success for the oil and gas industry is about safe drilling and operating to the best standards,'' he said in addressing the conference.
Pepanz and Freeman Media are assisting reporter Simon Hartley to attend the conference.
