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The Pouakai Range is an eroded and heavily vegetated
stratovolcano A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and p ...
in the
North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-larges ...
of
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 List of islands of New Zealand, smaller islands. It is the ...
, located northwest of
Mount Taranaki Mount Taranaki (), also known as Mount Egmont, is a dormant stratovolcano in the Taranaki region on the west coast of New Zealand's North Island. It is the second highest point in the North Island, after Mount Ruapehu. The mountain has a seco ...
. It consists of the remains of a collapsed
Pleistocene The Pleistocene ( , often referred to as the '' Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed ...
stratovolcano A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and p ...
. The range is surrounded by a ring plain of
lahar A lahar (, from jv, ꦮ꧀ꦭꦲꦂ) is a violent type of mudflow or debris flow composed of a slurry of pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a river valley. Lahars are extreme ...
deposits from a massive collapse that has been dated as roughly 250,000 years old. The region has been reshaped more recently after each cone collapse from
Mount Taranaki Mount Taranaki (), also known as Mount Egmont, is a dormant stratovolcano in the Taranaki region on the west coast of New Zealand's North Island. It is the second highest point in the North Island, after Mount Ruapehu. The mountain has a seco ...
.


Geology

The Pouakai Range volcano is situated in the Taranaki Basin and is part of the Taranaki Volcanic Lineament which has had a 30 mm/yr north to south migration over the last 1.75 million years. Present-day seismicity and stress directions in eastern Taranaki are consistent with back-arc extension processes. The Taranaki Volcanic Lineament members as they decrease in age from northwest to southeast are: # Paritutu, and the Sugar Loaf Islands from 1.75 Ma # Kaitake from 575 ka #Pouakai 210–250 ka #
Mount Taranaki Mount Taranaki (), also known as Mount Egmont, is a dormant stratovolcano in the Taranaki region on the west coast of New Zealand's North Island. It is the second highest point in the North Island, after Mount Ruapehu. The mountain has a seco ...
<200 ka


Volcanic activity

"After the extinction of the Kaitake center, eruptions broke out at Pouakai 6 miles south-east of Kaitake. Activity from this center continued over a long period of ring-plain formation, a period of marine erosion during which volcanic activity decreased, and part way through another period of ring-plain building, before activity broke out from the next center." It can be postulated that that all volcanoes in the Taranaki Volcanic Lineament have had a similar potential for instability and were stratovolcanoes of similar size and shape to the present Mount Taranaki between major collapse events given their debris plains. They may well have had major collapse cycles similar to that presently shown by
Mount Taranaki Mount Taranaki (), also known as Mount Egmont, is a dormant stratovolcano in the Taranaki region on the west coast of New Zealand's North Island. It is the second highest point in the North Island, after Mount Ruapehu. The mountain has a seco ...
which is a potential maximum size of collapse of every 30,000 to 35,000 years.


Nearby volcanoes

*
Sugar Loaf Islands The Sugar Loaf Islands (often Sugarloaf; mi, Ngā Motu, ) are a collection of five small uninhabited islands and several sea stacks near Port Taranaki, New Zealand. The largest, Moturoa Island, covers approximately . Motumahanga is the island ...
* Kaitake Volcano * Taranaki Volcano


References

{{reflist Mountain ranges of Taranaki Volcanoes of Taranaki Stratovolcanoes of New Zealand Pleistocene stratovolcanoes