Geology of New Zealand

New Zealand and New Caledonia represent the visible part of a portion of continental crust, usually referred to as Zealandia. The rest of Zealandia includes the Challenger Plateau and Lord Howe Rise, which stretch from Northwest of New Zealand almost to Northern Australia, and the Campbell Plateau and Chatham Rise, to the southeast of New Zealand.

The geology of New Zealand is noted for its volcanic activity, earthquakes and geothermal areas because of its position on the boundary of the Australian Plate and Pacific Plates. New Zealand is part of Zealandia, a microcontinent nearly half the size of Australia that broke away from the Gondwanan supercontinent about 83 million years ago.[1] New Zealand's early separation from other landmasses and subsequent evolution have created a unique fossil record and modern ecology.

New Zealand's geology can be simplified into three phases. First the basement rocks of New Zealand formed. These rocks were once part of the super-continent of Gondwana, along with South America, Africa, Madagascar, India, Antarctica and Australia. The rocks that now form the mostly submerged continent of Zealandia were then nestled between Eastern Australia and Western Antarctica.[2] Secondly New Zealand drifted away from Gondwana and many sedimentary basins formed, which later became the sedimentary rocks covering the geological basement. The final phase is represented by the uplift of the Southern Alps and the eruptions of the Taupō Volcanic Zone.[3]

  1. ^ Wallis, G. P.; Trewick, S. A. (2009). "New Zealand phylogeography: evolution on a small continent". Molecular Ecology. 18 (17): 3548–3580. Bibcode:2009MolEc..18.3548W. doi:10.1111/j.1365-294X.2009.04294.x. PMID 19674312. S2CID 22049973.
  2. ^ New Zealand within Gondwana from Te Ara: The Encyclopedia of New Zealand
  3. ^ "New Zealand Geology: an illustrated guide" (PDF). www.geotrips.org.nz.