Maori stones hold magnetic clues
Maori stones hold magnetic clues
Scientists are studying the Earth's magnetic field using the stones that line Maori steam ovens.
The cooking process generates so much heat that the magnetic minerals in these stones will realign themselves with the current field direction.
An archaeological search is under way in New Zealand to find sites containing old ovens, or hangi as they are known.
Abandoned stones at these locations could shed light on Earth's magnetic behaviour going back hundreds of years.
"We have very good palaeomagnetic data from across the world recording field strength and direction - especially in the Northern Hemisphere," said Gillian Turner from Victoria University, Wellington, New Zealand.
http://www.bbc.co.uk/news/science-environment-20520454