Mount Arthur (''Tuao Wharepapa'' in

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the C ...

) is in the

Wharepapa / Arthur Range The Wharepapa / Arthur Range is a mountain range partially marking the boundary between the Tasman District and West Coast Region of New Zealand's South Island. The range is at the eastern extent of the Tasman Mountains which make up much of t ...

in the north western area of the

South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. Mount Arthur, named after Captain Arthur Wakefield, lies within

Kahurangi National Park Kahurangi National Park in the northwest of the South Island of New Zealand is the second largest of the thirteen national parks of New Zealand. It was gazetted in 1996 and covers , ranging to near Golden Bay in the north. Much of what was the ...

and has a peak elevation of .

Geology

Mt Arthur is made of hard, crystalline

marble Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or Dolomite (mineral), dolomite. Marble is typically not Foliation (geology), foliated (layered), although there are exceptions. In geology, the ...

, transformed (hardened) from

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

, originally laid down under the sea some 450 million years ago in the

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start ...

. The "Arthur Marble" is part of the

Takaka Terrane The Takaka Terrane is a Paleozoic terrane that outcrops in the South Island of New Zealand. It is most extensively exposed within the Kahurangi National Park in the Tasman District. The terrane is mostly made up of marble and volcanic rocks but i ...

which was part of

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...

and is similar to rocks in modern-day south-east Australia. Below ground are some of the deepest shafts and most intricate

cave systems A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

in the country, and exploration of these is far from finished."Cobb Valley, Mt Arthur, Tableland"
Department Of Conservation. Retrieved 2015-01-12. Mount Arthur is home to the

Ellis Basin cave system The Ellis Basin cave system is a group of interconnecting limestone caves located in the Mount Arthur region of the northwest South Island of New Zealand. In April 2010, the cave system was found to be deeper than the nearby Nettlebed Cave, makin ...

, the deepest cave in the Southern Hemisphere, and

Nettlebed Cave __NOTOC__ Nettlebed Cave is a limestone cave located in the Mount Arthur region of the northwest South Island of New Zealand. The presence of ongaonga (''Urtica ferox''), an endemic tree nettle, near the bottom entrance gives the cave its name. ...

which was thought to be the deepest cave system the Southern Hemisphere prior to discovery of the Ellis Basin cave system in 2010. During the ice ages small glaciers carved smooth basins called '

cirque A (; from the Latin word ') is an amphitheatre-like valley formed by glacial erosion. Alternative names for this landform are corrie (from Scottish Gaelic , meaning a pot or cauldron) and (; ). A cirque may also be a similarly shaped landform ...

s' high on Mt Arthur, polishing and scraping the tough marble. The floors of the cirques are studded with

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...

s where surface water is taken underground into extensive cave systems.

References

External links

* {{DEFAULTSORT:Arthur Kahurangi National Park Mountains of the Tasman District

Geology

See also

References

External links