About 150 protesters blocked the main entrances to the SkyCity Convention Centre this morning, with 20 entering the conference centre, but no arrests have been made and a visible police presence has ensured most, but not all, delegates have been able to enter the building.
Greenpeace New Zealand invited the public to take part in "civil disobedience action en masse" against petroleum exploration, which the group says damages the environment by accelerating climate change.
Protest leader Steve Abel said he apologised to members of the public affected by the sit-in, but not the oil industry representatives at the conference.
About 60 people have been issued with trespass orders and the police forced an opening through the protesters to allow delegates inside.
Bridges says the NZ government backs exploration, because oil exports are one of the nation's biggest export earners, while gas helps displace coal.
He hopes oilers will embrace the latest lease offer, which covers areas in the offshore Northland-Reinga Basin, Taranaki Basin Pegasus/East Coast basins and Great-South/Canterbury basins, and some 1062sq.km of the onshore Taranaki Basin.
"If there is one benefit [from the downturn], it is that difficulty breeds innovation. You have to come up with different ways of doing things. These circumstances will help make the industry more resilient and set it in better stead for the future," he said.
"And some of the activity going on right now is a vote of confidence in the future of the industry. For example, Shell's Caledonia Basin seismic survey is providing never-known-before scientific information in the most frontier of basins.
"The uptake of acreage in recent years, for example in the Pegasus and East Coast basins, is also very promising. We have attracted some very highly regarded international companies and I look forward to their exploration work progressing in the coming years. While on Pegasus, I was pleased to see Statoil are showing further interest in this basin, with their planned farm-in to OMV's permit."
Bridges says NZ must be open to getting the balance right between fossil fuels and renewables, and he believes there is a big gas story developing.
"For a long time New Zealand has been considered, rightly or wrongly, "gas-prone". These days that label may work more in our favour," Bridges said.
"As the cleanest fossil fuel, countries are increasingly choosing gas as an alternative to coal for electricity generation. According to the United States Environmental Protection Agency, greenhouse gas emissions fell to their lowest level in 17 years in the world's largest economy, largely due to a rapid drop in coal-fired electricity, and the rise of electricity generated by cleaner fuels, particularly natural gas.
"The International Energy Agency predicts natural gas demand will continue its expansion as the fastest growing fossil fuel, and speak of it as a very important bridging fuel to a lower-carbon global economy."
He said a big gas discovery could see NZ sending LNG off to Asia.
Block Offer 2016, the fourth since a new leasing system was enacted in 2012, is offering up to 525,500sqkm of largely frontier areas.
Past offers have seen 44 permits awarded, and attracted new operators to NZ's shores including Chevron Corporation, Statoil, Woodside Petroleum and ONGC Videsh.
The Pegasus and East Coast basins are considered among NZ's most promising areas.
Both are prospective for oil, gas, and gas hydrates gas, and both are under-explored, while the Northland- Reinga Basin is believed to be prospective for oil and gas, and it shares a lot in common with the Taranaki Basin.
The Taranaki Basin is a proven province, host to all of NZ's big discoveries - Maui, Pohokura, Kupe Tui and Maari - but there is still plenty of scope for further exploration upside, Bridges said.
The areas in the offer were selected based on formal nominations received from industry and other interested parties, and the data that is available about the geological prospectivity of the areas.
Bids are due by September 7.
Since the mid-1970s New Zealand has produced 510 million barrels of crude, condensate and natural gas liquids; and almost 7000 petajoules of natural gas and paid billions of dollars in royalties and taxes to the government - all from the Taranaki Basin, with 18 other basins almost entirely unexplored.
