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"Pushed up in the collision of the Australian
and Pacific tectonic plates, finely sculptured by westerly rains,
and still showing the imprint of pleistocene glaciations, New
Zealand's mountain landscapes are among the most dynamic and
spectacular in the world. Compared with the continental mountains
of Europe and America the mountains are younger, much sharper
textured, and are being shaped with a tempo that can be measured
in decades rather than centuries or millenia" From
I.E Whitehouse and A.J. Pearce: Shaping the Mountains of New
Zealand, in J.M. Soons and M.J. Selby 1992: Landforms of New
Zealand Second Edition.
Mountains are one of the dominant features
in the New Zealand landscape. Sixty percent of the South Island,
and twenty percent of the North Island, can be classified as
mountain land. Most of it stands over 600 metres altitude (2000
feet), and most is steep land.
The mountains in New Zealand result from the
collision between the Australian and Pacific tectonic plates,
and their location follows the boundary of the two plates. Thus
a continuous chain of mountains forms the axial part of the
South Island, extending over 750 km (500 miles) from the Kaikoura
Ranges, through the length of the Southern Alps, to the southernmost
corner of Fiordland.
In the east of the North Island the axial ranges extend in a
uninterrupted chain, from Wellington and the Rimutaka Ranges
in the south to the Tararua, Ruahine, Kaimanawa-Kaweka, and
Raukumara Ranges in the north.
While located outside the axial area, the other major mountain
ranges of New Zealand also originate in the same plate tectonic
process: they are the Central Otago ranges, Paparoa, Victoria,
North-west and East Nelson in the South Island, and the two
large volcanic centres of Mt Egmont, and Ruapehu-Tongariro in
the North Island.
See also: Tectonics
in New Zealand
The distinctive character of the mountains
of New Zealand result from the combination of the following
factors:
- the plate tectonic processes already mentioned,
- climatic conditions, in particular the high precipitation
and rainfall produced by the combination of a dominant westerly
flow with the high barrier of the mountain ranges,
- the nature and variations of rock types and geological structures,
- the action in the landscape of the glaciers and other agents
that were at work during the glacial ages.
Finally, the specific character of New Zealand's native vegetation
also contributes to the character of the mountains.
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