38-453: Tokaanu is a small settlement close to Tūrangi at the southern end of Lake Taupō . The Tokaanu Thermal Pools and the easy access to Lake Taupo make it a popular lakeside holiday destination. A short walking track through the Tokaanu thermal area leads past steaming hot mineral pools and small mud pools dotted amongst the native bush. To the east of Tokaanu, another short walking track leads up
76-475: A Waihora outlet to the northwest, cut through its Oruanui ignimbrite dam near the present Taupō outlet to the northeast at a rate which left no terraces around the lake. About 60 km (14 cu mi) of water was released, leaving boulders of up to 10 m (33 ft) at least as far down the Waikato River as Mangakino . The impact has been summarised as: The Oruanui eruption ash deposits from
114-525: A correlation, to within a few years, of a year in which the sky was red over Rome and China . The eruption devastated much of the North Island and further expanded the lake. The area was uninhabited by humans at the time of the eruption, as New Zealand was not settled by Māori until about 1280. Possible climatic effects of the eruption would have been concentrated on the Southern Hemisphere due to
152-551: A food for the trout. A community of sponges and associated invertebrates live around the underwater geothermal vents. Tourism is a major component of Taupō's commercial sector. The busiest time for the industry is the high summer season around Christmas and New Year. The lake area has a temperate climate. Daily maximum temperatures recorded for Taupō range from an average of 23.3 °C in January and February to 11.2 °C in July, while
190-423: A melt dominant magma body that formed at between 3.5–6 km (2.2–3.7 mi) depth. There is emerging evidence that much of the silicic magma produced was formed deeper than this in the middle or lower crust (some have suggested as deep as the upper mantle) and ascending rapidly to this magma reservoir with only brief storage there. The relative uniformity of the eruptives (99% high-SiO 2 rhyolite), suggests
228-417: A minimum flow of 50 m /s (1,800 cu ft/s) in the Waikato River. The resource consent allows the level of the lake to be varied between 355.85 and 357.25 metres (1,167.5 and 1,172.1 ft) above sea level. Lake Taupō is in a caldera created mainly by a supervolcanic eruption which occurred approximately 25,600 years ago. According to geological records, the volcano has erupted 29 times in
266-490: Is a stub . You can help Misplaced Pages by expanding it . Lake Taup%C5%8D Lake Taupō (also spelled Taupo ; Māori : Taupō-nui-a-Tia or Taupōmoana ) is a large crater lake in New Zealand 's North Island , located in the caldera of Taupō Volcano . The lake is the namesake of the town of Taupō , which sits on a bay in the lake's northeastern shore. With a surface area of 616 km (238 sq mi), it
304-466: Is concealed beneath Lake Taupō, while the lake outline at least partly reflects volcano-tectonic collapse. Early eruption phases saw shifting vent positions; development of the caldera to its maximum extent (indicated by lithic lag breccias ) occurred during phase 10. The Oruanui eruption shows many unusual features: its episodic nature, a wide range of magma-water interaction, and complex interplay of pyroclastic fall and flow deposits. The erupted magma
342-574: Is the largest lake by surface area in New Zealand , and the second largest freshwater lake by surface area in geopolitical Oceania after Lake Murray in Papua New Guinea . Motutaiko Island lies in the southeastern area of the lake. Lake Taupō has a perimeter of approximately 193 km (120 mi) and a maximum depth of 186 m (610 ft). It is drained by the Waikato River (New Zealand's longest river), and its main tributaries are
380-454: Is the largest phreatomagmatic eruption characterised to date. The eruption is divided into 10 different phases on the basis of nine mappable fall units and a tenth, poorly preserved but volumetrically dominant fall unit. Modern-day Lake Taupō , 616 km (238 sq mi) in area and 186 m (610 ft) deep, partly fills the caldera generated during this eruption. A 140 km (54 sq mi) structural collapse
418-456: Is up to 200 metres (660 ft) deep. Ashfall affected most of New Zealand, with an ash layer as thick as 18 centimetres (7 in) deposited on the Chatham Islands , 850 km (530 mi) away. The local biological impact must have been immense as 10 centimetres (4 in) of ash was deposited from just south of Auckland over the whole of the rest of the North Island, and the top of
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#1732869134118456-600: The Chatham Islands . The first characterised eruption from the Taupō Volcano after the Oruanui eruption took place about 5000 years later. The first three eruptions were dacitic as was the Puketarata eruption . The other twenty-four rhyolitic events until the present, including the major Hatepe eruption, dated to around 232 CE came from three distinct magma sources. These have had geographically focussed vent locations, and
494-578: The Hatepe eruption , it is believed to have ejected 100 cubic kilometres of material, of which 30 cubic kilometres was ejected in a few minutes. This was one of the most powerful eruptions in the last 5000 years (alongside the Minoan eruption in the 2nd millennium BCE, the Tianchi eruption of Baekdu around 1000 CE and the 1815 eruption of Tambora ), with a Volcanic Explosivity Index rating of 7; and there appears to be
532-483: The Kawakawa eruption or Kawakawa/Oruanui event ) was the world's most recent supereruption , and largest phreatomagmatic eruption characterised to date. At the time of the eruption sea level was much lower than at present and the Taupō Volcano had been for over 100,000 years mainly located under a larger lake than the present Lake Taupō called Lake Huka . Lake Huka was destroyed in the eruption and other features of
570-749: The South Island , both of which were larger in land area as sea levels were considerably lower than present. The pyroclastic ignimbrite flows destroyed all vegetation they reached. Later erosion and sedimentation had long-lasting effects on the landscape and may have caused the Waikato River to shift from the Hauraki Plains to its current course through the Waikato to the Tasman Sea . Less than 22,500 years ago, Lake Taupō, having filled to about 75 m (246 ft) above its current level, and draining initially via
608-583: The Waitahanui River , the Tongariro River , and the Tauranga Taupō River . It is a noted trout fishery with stocks of introduced brown and rainbow trout . The level of the lake is controlled by Mercury Energy , the owner of the eight hydroelectric dams on the Waikato River downstream of Lake Taupō, using gates built in 1940–41. The gates are used to reduce flooding, conserve water and ensure
646-411: The 40.2 km length of the lake is a challenge for open-water swimmers. In 2020, Michael Wells from Darwin, Australia, was the first to breaststroke across the lake. On the north-west side of Lake Taupō on the cliffs of Mine Bay, there are Māori rock carvings created in the late 1970s by Matahi Whakataka-Brightwell and John Randall. Carved in the likeness of Ngātoro-i-rangi , a navigator who guided
684-485: The 490 m high Manganamu, an extinct lava dome. Before the development of Tūrangi in the 1960s, Tokaanu was the main settlement at the southern end of Lake Taupo. It had been known to Māori for centuries for its natural thermal pools. The pools became a major stopover on the Grand Tour stage coach run from Wanganui to Taupō in the 1800s. Passengers arrived by stage coach from Waiouru , and departed by steam launch from
722-400: The Oruanui magma body had been vigorously convecting by the time of the eruption. Nonetheless composition analysis shows that three different rhyolites contributed, with the initial two phases of the eruption having contributions from a leak of biotite-bearing rhyolite, presumably along dykes at more than 2 km (1.2 mi) depth, associated with tectonic faulting from a magma chamber to
760-533: The Te Arawa waka. Ngāti Tūwharetoa owns the bed of the lake and its tributaries. They grant the public free access for recreational use. Lake Taupō previously housed a Ngāti Tūwharetoa village known as Te Rapa near the springs of Maunga Kākaramea . It was covered in a landslide on 7 May 1846 which killed 60 people, including the iwi's chief Mananui Te Heuheu Tūkino II . Oruanui eruption The Oruanui eruption of New Zealand 's Taupō Volcano (also known as
798-516: The Tūwharetoa and Te Arawa tribes to the Taupō area over a thousand years ago according to Māori legend . The 10-metre-high carving is intended to protect Lake Taupō from volcanic activities underneath. The cliff has become a popular tourist destination with hundreds of boats and yachts visiting the spot yearly. Lake Taupō is a taonga (treasure or something special to the person) of Ngāti Tūwharetoa from
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#1732869134118836-405: The caldera. The caldera later filled with water to form Lake Taupō, eventually overflowing to cause a huge outburst flood . Several later eruptions occurred over the millennia before the most recent major eruption, which was traditionally dated as about 181 CE from Greenland ice-core records. Tree ring data from two studies suggests a later date of 232 CE ± 5 and this is now accepted. Known as
874-404: The deposits contain volcanic ash aggregates . The timescale for the growth of the assumed Oruanui mush zone , which has a distinctive chemical and isotopic composition and zircon model-age spectra is now known to be from about 40,000 years ago from earlier Taupō Volcano eruptions. During crystal-liquid separation in this mush, large volumes of melt and crystals were carried upwards into
912-470: The eastern alignment of the later Hatepe eruption , and the 4th vent was more central. The later stages of the eruption may have had venting from much of what is now the northern part of Lake Taupō. While pyroclastic density currents were generated throughout the eruption, the peak distance reached in ignimbrite deposits was about 90 km (56 mi) during phase 8. This phase, as well as several others, before phase 10, were not that much smaller than
950-524: The eruption itself or some have suggested Lake Taupō had separated with a higher level than the remaining Lake Huka about a thousand years earlier, due solely to eruptive activity of the Poihipi volcano adjoining Mount Tauhara whose magma chamber is under Wairakei and that had erupted at Trig 9471 and the Rubbish Tip Domes about 27,000 years ago, filling that portion of Lake Huka. Accordingly, many of
988-501: The final (tenth) phase have been geochemically matched to Western Antarctic ice core deposits 5,000 km (3,100 mi) away and they provide a convenient marker for the last glacial maximum in Antarctica . This ash cloud has been modelled to have taken about two weeks to encircle the Southern Hemisphere . Diatoms from erupted lake sediments have been found in the volcanic ash deposits about 850 km (530 mi) downwind on
1026-405: The final eruption priming appear to be only decades long at most. The eruption itself lasted only a few months, with most of the stages as described below being continuous. The location of the eruptive vents are only known for the first four stages of the eruption. Vents during stage 1 and 2 were in the north-east portion of present Lake Taupō, a third vent (or more likely several vents) was closer to
1064-663: The historic Tokaanu wharf onwards to Taupo. The Tokaanu Power Station , the largest hydro dam in the Tongariro power scheme, was built in the area in the 1960s. The local Tokaanu Marae and Puhaorangi meeting house is a meeting place of the Ngāti Tūwharetoa hapū of Ngāti Kurauia. Tokaanu is part of the Lake Taupo Bays statistical area. 38°57′58″S 175°46′05″E / 38.966°S 175.768°E / -38.966; 175.768 This Waikato geography article
1102-400: The lake include northern kōura or crayfish ( Paranephrops planifrons ) and kōkopu or whitebait ( Galaxias species). The lake is noted for stocks of brown trout ( Salmo trutta ) and rainbow trout ( Oncorhynchus mykiss ), introduced from Europe and California respectively in the late nineteenth century. There has also been a subsequent introduction of smelt ( Retropinnidae species) as
1140-512: The last 30,000 years. It has ejected mostly rhyolitic lava , although Mount Tauhara formed from dacitic lava. Taupō has been active for 300,000 years with a very large event known as the Oruanui eruption occurring approximately 25,600 years ago. It was the world's largest known eruption over the past 70,000 years, ejecting 1170 cubic kilometres of material and causing several hundred square kilometres of surrounding land to collapse and form
1178-437: The later Hatepe eruption of the Taupō Volcano. Ash (Kawakawa tephra) distributed during the various stages created a stratigraphic layer found over much of New Zealand and its surrounding sea bed as wind direction varied, the eruptive columns were so high, and the volumes of ash were so large. Tephra from the eruption covered much of the central North Island and is termed Kawakawa-Oruanui tephra, or KOT. The Oruanui ignimbrite
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1216-812: The local geography were changed significantly as outlined below. With a Volcanic Explosivity Index of 8, it is one of the largest eruptions ever to occur in New Zealand and the most recent supereruption . It occurred 25 675 ± 90 years BP in the Late Pleistocene and generated approximately 430 km (100 cu mi) of pyroclastic fall deposits, 320 km (77 cu mi) of pyroclastic density current (PDC) deposits (mostly ignimbrite ) and 420 km (100 cu mi) of primary intracaldera material, equivalent to 530 km (130 cu mi) of rhyolitic magma , totalling 1,170 km (280 cu mi) of total deposits. As such it
1254-442: The magma formed deeper, the maturing temperature was about 900 °C. About 0.5% of the eruptives was low-SiO 2 rhyolite believed to have been tapped from isolated pockets in the underlying crystal mush. Two distinct mafic magmas were involved in the eruption, and a total volume of 3–5 km (0.72–1.20 cu mi) of mafic magma is atypically high compared to other nearby rhyolitic eruptions. The timescales involved in
1292-610: The nighttime minimum temperatures range from 11.6 °C in February down to 2.2 °C in July. Rain falls in all seasons but is greatest in winter and spring, from June to December. Taupō hosts the Lake Taupo Cycle Challenge , a cycling tour around the lake which can take anywhere between four and ten hours. Skydiving is a popular local sport and tourist attraction. Taupō also hosts the ANZCO Ironman event. Crossing
1330-466: The north. The biotite-bearing rhyolite composition is like that found within the Maroa Caldera adjacent to the Taupō Volcano. These initial stages were from magma at relatively low overpressure and if stored and matured in a shallow magma chamber had a temperature of about 780 ± 20 °C, with between a week to two weeks ascent of magma before eruption. It is possible that if the later majority of
1368-578: The site of occurrence of certain extremophile micro-organisms, that are capable of surviving in extremely hot environments. The volcano is considered active and is monitored by GNS Science. Much of the watershed of Lake Taupō is a beech and podocarp forest with associate understory ferns being Blechnum filiforme , Asplenium flaccidum , Doodia media , Hymenophyllum demissum , Microsorum pustulatum and Dendroconche scandens , and some prominent associate shrubs being Olearia rani and Alseuosmia quercifolia . Native faunal species in
1406-607: The southerly position of Lake Taupō. Taupō's last known eruption occurred around 30 years later, with lava dome extrusion forming the Horomatangi Reefs , but that eruption was much smaller than the Hatepe eruption. Underwater hydrothermal activity continues near the Horomatangi vent, and nearby geothermal fields with associated hot springs are found north and south of the lake, for example at Rotokawa and Tūrangi . These springs are
1444-462: Was very uniform in composition and this composition has not been seen since but had been seen before the eruption. Detailed compositional analysis has revealed the early phases of the eruption had a small amount of magma from outside the Taupō Volcano and are most consistent with a tectonic trigger. The eruption occurred through a lake system which was either the southern section of Lake Huka, recently separated by pre-eruption upwarping shortly before
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