Under the prospecting permit exclusion, just put in place by Minister of Energy and Resources Simon Bridges, permits covering mineral exploration and mining can still be applied for.
The aeromagnetic data helps identify mineral deposits and provides information on faults, aquifers and soils. Aeromagnetic data is derived from measuring both the earth's magnetism from place to place and mapping variations in naturally occurring radiation.
Of the total $8million being spent on new data, about $6.4million is going towards the aeromagnetic and soil sampling.
NZPM manager commercial, analysis and investment David Darby said in his latest update that the Murchison survey would create a link between the Nelson and Marlborough surveys, and the Government's 2013 survey of the West Coast.
''Once complete, we will have a seamless data-set linking Nelson and Marlborough with the West Coast.
''It will mean aeromagnetic data has been gathered over more than 30% of the country,'' Mr Darby said in a statement.
The data gathered is available, free, to industry and provided valuable information for potential investors which could help sway investment decisions, he said.
NZPM similarly undertakes seaborne hydrographic surveys of the seabed, which was also to entice oil and gas explorers to New Zealand.
The exclusion of applying for prospecting permits runs from last September to July 2018, with the reservations in total covering more than 17,626sq km.
Mr Bridges said prospecting permits for metallic minerals would not be granted or extended in relation to three separate areas of land around the South Island, including the reserve areas in Otago and Murchison.
Under the wider aeromagnetic survey, undertaken by helicopters and fixed-wing aircraft, areas being covered included east Nelson, Murchison, North and Central Otago and South Otago and Southland.
The Otago Southland survey started in January and was now more than 45% complete and would restart again in the summer of 2016-17.
The North Otago part of the survey restarted in mid-September and was expected to be completed by November.
''So far, this part of the survey has acquired approximately 53,000 line km of geophysical data,'' NZPM said in a statement.
The Marlborough District Council and Venture Southland, representing Environment Southland, Southland District Council, Invercargill City Council and Gore District Council, had partnered NZPM on the project, which would provide them with information on geological hazards, including fault lines, regional water resources and information on climate, soil and geology.
