Study identifies 48 faults in Otago region

Study identifies 48 faults in Otago region | Insurance Business New Zealand

Study identifies 48 faults in Otago region

A total of 48 earthquake faults have been identified in the Central Otago and Queenstown Lakes areas, it has been revealed.

In a new report presented to Otago Regional Council, 21 identified faults were described as “definite” or “likely” faults, six were classed as “possible” active faults and another 21 were “potentially active.” The most active faults were the northwest Cardrona fault, with a recurrence interval of 5,500 years, and the Lindis Pass fault zone, at 5,600 years, Otago Daily Times reported.

The northwest Cardrona fault was reportedly re-mapped as extending north from the Cardrona valley, near the foot of the Mt Alpha range, and through the middle of Wanaka. It was formerly known to extend northeast to Lake Hawea, passing beneath Albert Town and part of the Lake Hawea township.

The other seven faults which had a recurrence interval of less than 10,000 years were the Dunstan fault zone, Gimmerburn fault zone, Highland fault, Livingstone fault, Motatapu fault, Nevis fault zone, and the Timaru Creek fault.

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Otago Daily Times noted the Moonlight fault, a major Queenstown fault, was significantly downgraded as having a recurrence interval of more than 100,000 years. It was previously regarded as one of the most active faults in the area, with a recurrence interval of between 6,000 and 7,000 years.

The work was part of a region-wide review which was broken down into districts, council natural hazards analyst Ben Mackey told the publication.