Surveying sediment: The team of scientists from University of Otago work at a 25m trench site near the Nevis Valley


The impacts of a rupture on the Nevis Fault could be ‘‘far more severe’’ than those from the Alpine Fault, Queenstown council’s risk and resilience boss, Bill Nicoll, says.

New research shows a rupture of the 100-kilometre fault, which stretches from Wānaka
to Garston, could cause an earthquake similar in scale to the magnitude-7.1 2010  Canterbury quake.

Funded by the Earthquake Commission, an Otago Uni team excavated sites in the Upper Nevis Basin to analyse sediment layers, unearthing proof of at least two major prehistoric seismic events, indicating the fault’s got the potential to produce an  earthquake over magnitude 7.

Nicoll says the potential losses on the region’s three waters network alone would be significant.

While the Alpine Fault remains a focus due to its size, Nicoll says planning’s underway to manage the potential impacts of local fault lines, like the Moonlight and the Nevis and council’s buying new mobile satellite wireless systems and Sentinal earthquake-monitor
ing sensors for Queenstown Events Centre and Wānaka Recreation Centre.

Lead researcher, seismologist Mark Stirling, says awareness is key to preparedness.

While the Alpine Fault is the ‘‘rock star of faults’’ in the South, residents need to be aware of other local seismic hazards, he says.