Credit: Julian Thomson

A large earthquake that rocked New Zealand's South Island in 2016 was one of the most complex ever recorded, involving the rupture of at least 12 major faults.

A team led by Ian Hamling of GNS Science in Lower Hutt, New Zealand, used field mapping, satellite observations and other measurements to analyse the magnitude-7.8 quake (pictured), which struck on 14 November. They studied the network of geological faults that ruptured along more than 170 kilometres during the quake. They found that many more faults broke, and at greater depths, than the country's national seismic-hazard model suggested was possible.

Officials in other parts of the world may want to reassess their local earthquake risk, the authors suggest.

Science http://doi.org/b4r7 (2017)