New Zealand Plate Tectonics

Extreme Earth Events - 12ESS

Finn LeSueur

2021

NZ Plate Tectonics

Collect a poster from the front, open Google Classroom to the task and use the resources to help you answer your questions and label New Zealand. There are also some slides following this one which will help you.

Pacific and Australian Plates

  • New Zealand lies at the edge of both the Australian and Pacific tectonic plates.
  • To the northeast of New Zealand, and underneath North Island, the Pacific Plate is moving towards, and being subducted below the Australian Plate.
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To the south of New Zealand, and underneath Fiordland, the two plates are also moving toward each other but here the Australian Plate is being subducted under the Pacific Plate.

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Kermadec Trench

  • The subduction in the north causes the formation of the kermadec trench. Underwater volcanoes are formed under water except for Raoul island. Note the sea level.
  • Huge cone volcanoes (approx 2, 800m) rise up from the ocean floor. Many have large craters, formed by powerful eruptions.
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This subduction also results in the Taupo Volcanic Zone + shallow trenches such as the Hikurangi trough

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The deepest trench in NZ is the 6,000-metre deep Puysegur Trench. Oceanic crust of the Australian Plate dives beneath the Pacific Plate. It is a mirror image of the Kermadec Trench to the north-east.

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Continental crust colliding with continental crust. Both are light so neither subduct. Mountain ranges such as the Southern Alps are thrust up instead.

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Map Labels

  • Alpine fault
  • White Island
  • Mt Taranaki
  • Taupo volcanic zone
  • Auckland volcanic field
  • Kermadec trench
  • Puysegur trench
  • Hikurangi subduction zone
  • Mt Ruapehu
  • Lake Taupo
  • Marlborough fault system
  • Banks peninsula volcano complex