Overview and Current Tectonic Setting



New Zealand is located at a subduction zone. Under the North Island (where Auckland is located), the Pacific plate is being subducted underneath the Australian plate. In contrast, the under the South Island, the Australian plate is being subducted under the Pacific plate. A major feature of the South Island is the Alpine fault, which forms the boundary between these two plates. This is a strike-slip fault (plates move side by side), and a large mountain region is located at the fault, uplifting slightly each year.

With these tectonic features in mind, Auckland is susceptible to a variety of geological hazards, including but not limited to: slope instability, seismic, volcanic and tsunami hazards.

The movement of these plates means that Auckland and New Zealand in general is greatly at risk of earthquakes.  In addition, there is also a long history of volcanic activity in this area due to subducting plates. In fact, Auckland sits on one of the most densely packed volcanic fields in the world, known as the Auckland Volcanic Field (AVF), home to over 50 volcanoes. The majority of these volcanoes erupt only once, and while the field is currently dormant, there is a risk it could reactivate.

Image depicting modern New Zealand (green), plate boundaries (dotted red) and the part of the Zealandia continent (grey dotted line). Retrieved from:https://en.wikipedia.org/wiki/Geology_of_New_Zealand#/media/File:Zealandia-Continent_map_en.svg


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  1. UnknownMarch 28, 2019 at 6:19 PM

    https://www.gns.cri.nz/Home/Our-Science/Earth-Science/Plate-Tectonics/NZ-plate-boundary

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