He was "taken by surprise" by a recent big surge of international media interest in his paper, which pointed out that New Zealand was part of a huge underwater continent, Zealandia, Dr Mortimer said.
Zealandia, a continent two-thirds the size of Australia, had been found beneath the southwest Pacific Ocean, scientists reported in the journal of the Geological Society of America.
The land mass of 4.5 million square kilometres was 94% underwater and only its highest points — most notably New Zealand and New Caledonia — poked above the surface.
Dr Mortimer and another two of the paper’s 11 authors, Dr Andy Tulloch and Dr Chris Adams, are based at GNS’ Dunedin research centre. The global interest had "taken us all by surprise", Dr Mortimer said.
But none of that media interest had been "engineered by us".
"It arose from a one-paragraph newsfeed by the Geological Society of America and has mushroomed from there."
He was "stunned" by the response, which was "quite thrilling", and he had been contacted by about 30 media outlets throughout the world.
English-born, Dr Mortimer has worked as a government geologist in New Zealand for more than 30 years, and has been part of the regional geology team at GNS’ Dunedin centre since 1994.
Many New Zealanders were already aware of the existence of Zealandia.
"But I guess it’s brand new to most non-NZers and the concept of a hidden or drowned continent captures the imagination.
"We write in the paper: ‘Zealandia illustrates that the large and the obvious in natural science can be overlooked’.
"I think this struck a chord with people who had never heard of Zealandia before."
Zealandia was the "thinnest, most submerged and smallest continent".
It would take time but, "we hope that Zealandia will eventually make its way on to general world maps, be taught in schools and become as familiar a name as Antarctica."
