The culprit behind a recent swarm of earthquakes in New Zealand’s Bay of Plenty has been found: a growing bubble of magma less than 10 kilometres below ground. Geophysicists from the New Zealand research institute GNS Science, led by Ian Hamling, tracked how the ground lifted and sank in the Taupo Volcanic Zone, a 30-kilometre zone that runs northeast from the centre of the North Island to the Bay of Plenty coast.

They saw the northern section deformed in a way consistent with a ballooning reservoir of magma beneath. “There is every possibility the magma body under the Bay of Plenty coast had been there for centuries, and possibly even longer,” Hamling says. FULL REPORT