72-603: The relatively small Rotomā Caldera (also known as Rotomā Embayment , Rotomā volcanic complex , and spelled Rotoma ) is in the Taupō Volcanic Zone in the North Island of New Zealand. The Rotomā Caldera is located halfway between the city of Rotorua and town of Whakatāne , with its in filling Lake Rotomā being the easternmost in the chain of three volcanic lakes to the northeast of Lake Rotorua . The other two are Lake Rotoiti and Lake Rotoehu . The Rotomā Caldera
144-464: A buffer that breaks apart the plume. Any heat from the plume that does make it to the surface is limited. Volcanic and tectonic actions in the region cause between 1,000 and 2,000 measurable earthquakes annually. Most are relatively minor, measuring magnitude 3 or weaker. Occasionally, numerous earthquakes are detected in a relatively short period of time, an event known as an earthquake swarm . In 1985, more than 3,000 earthquakes were measured over
216-579: A hundred or so lava extruding eruptions per million years, and "several to many" steam eruptions per century. The loosely defined term " supervolcano " has been used to describe volcanic fields that produce exceptionally large volcanic eruptions. Thus defined, the Yellowstone Supervolcano is the volcanic field that produced the latest three supereruptions from the Yellowstone hotspot; it also produced one additional smaller eruption, thereby creating
288-466: A magnitude 4.8 earthquake struck Yellowstone, the largest recorded there since February 1980. In February 2018, more than 300 earthquakes occurred, with the largest being a magnitude 2.9. The Lava Creek eruption of the Yellowstone Caldera, which occurred 640,000 years ago, ejected approximately 1,000 cubic kilometres (240 cu mi) of rock, dust and volcanic ash into the atmosphere. It
360-600: A magnitude of 3.9. Another swarm started in January 2010, after the Haiti earthquake and before the Chile earthquake . With 1,620 small earthquakes between January 17, 2010, and February 1, 2010, this swarm was the second-largest ever recorded in the Yellowstone Caldera. The largest of these shocks was a magnitude 3.8 that occurred on January 21, 2010. This swarm subsided to background levels by February 21. On March 30, 2014, at 6:34 AM MST ,
432-419: A period of several months. More than 70 smaller swarms were detected between 1983 and 2008. The USGS states these swarms are likely caused by slips on pre-existing faults rather than by movements of magma or hydrothermal fluids. In December 2008, continuing into January 2009, more than 500 earthquakes were detected under the northwest end of Yellowstone Lake over a seven-day span, with the largest registering
504-859: A significant distance beyond the caldera proper. The caldera formed during the last of three supereruptions over the past 2.1 million years: the Huckleberry Ridge eruption 2.1 million years ago (which created the Island Park Caldera and the Huckleberry Ridge Tuff ), the Mesa Falls eruption 1.3 million years ago (which created the Henry's Fork Caldera and the Mesa Falls Tuff ), and the Lava Creek eruption approximately 640,000 years ago (which created
576-405: A substantial contribution to the development of geological sciences through history". The source of the Yellowstone hotspot is controversial. Some geoscientists hypothesize that the Yellowstone hotspot is the effect of an interaction between local conditions in the lithosphere and upper mantle convection . Others suggest an origin in the deep mantle ( mantle plume ). Part of the controversy
648-492: A succession of explosive eruptions and less violent floods of basaltic lava . Together these eruptions have helped create the eastern part of the Snake River Plain (to the west of Yellowstone) from a once-mountainous region. At least a dozen of these eruptions were so massive that they are classified as supereruptions . Volcanic eruptions sometimes empty their stores of magma so swiftly that the overlying land collapses into
720-670: A total volume of 78 km (19 cu mi). The central part of the zone is composed of eight caldera centres the oldest of which is the Mangakino caldera which was active more than a million years ago (1.62–0.91 Ma). This produced ignimbrite that 170 km (110 mi) away in Auckland is up to 9 m (30 ft) thick. Other than the now buried Kapenga caldera there are five caldera centres, Rotorua, Ohakuri, Reporoa, Ōkataina and Taupō. These have resulted from massive infrequent eruptions of gaseous very viscous rhyolite magma which
792-524: A way that could be used as a geothermal power source. If enacted, the plan would cost about $ 3.46 billion. Brian Wilcox of the Jet Propulsion Laboratory observes that such a project could incidentally trigger an eruption if the top of the chamber is drilled into. Studies and analysis may indicate that the greater hazard comes from hydrothermal activity which occurs independently of volcanic activity. Over 20 large craters have been produced in
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#1732897728828864-813: A zone known as the Taupō Rift. Volcanic activity continues to the north-northeast, along the line of the Taupō Volcanic Zone, through several undersea volcanoes in the South Kermadec Ridge Seamounts , then shifts eastward to the parallel volcanic arc of the Kermadec Islands and Tonga . Although the back-arc basin continues to propagate to the south-west, with the South Wanganui Basin forming an initial back-arc basin, volcanic activity has not yet begun in this region. South of Kaikōura
936-548: Is considered its northeastern limit. It forms a southern portion of the active Lau-Havre-Taupō back-arc basin , which lies behind the Kermadec-Tonga Subduction Zone . Mayor Island and Mount Taranaki are recently active back arc volcanoes on the New Zealand extension of this arc. Mayor Island / Tūhua is the northern-most shield volcano adjacent to the New Zealand coast, and is believed to have been active in
1008-490: Is estimated to have been ejected in just a few minutes. The date of this activity was previously thought to be 186 AD as the ash expulsion was thought to be sufficiently large to turn the sky red over Rome and China (as documented in Hou Han Shu ), but this has since been disproven. Whakaari / White Island had a major, edifice failure collapse of its volcano dated to 946 BCE ± 52 years. It has been suggested that this
1080-431: Is exhibited via numerous geothermal vents scattered throughout the region, including the famous Old Faithful Geyser , plus recorded ground-swelling indicating ongoing inflation of the underlying magma chamber. The volcanic eruptions, as well as the continuing geothermal activity, are a result of a great plume of magma located below the caldera's surface. The magma in this plume contains gases that are kept dissolved by
1152-510: Is formed from numerous volcanic deposits created by slope failure, eruptions, or lahars . Northwest of Ruapehu is Hauhungatahi , the oldest recorded volcano in the south of the plateau, with to the north the two prominent volcanic mountains in the Tongariro volcanic centre being Tongariro and Ngauruhoe which are part of a single composite stratovolcano . The most likely risk is earthquake associated with multiple active faults, such as within
1224-503: Is immediately to the northeast of the area previously called the Haroharo volcanic complex, and now known as the Haroharo vent alignment . This is now regarded as part of the much larger Ōkataina Caldera ( Ōkataina Volcanic Centre). It has been usually classified as part of this volcanic structure, but given the evidence that it is a region of structural collapse beyond the Ōkataina Caldera rim
1296-515: Is known that the changes in vegetation following the eruption, while significant, were short-lived. Pre-eruption forest and mire vegetation recovering to former levels within about 106 years. Taup%C5%8D Volcanic Zone The Taupō Volcanic Zone ( TVZ ) is a volcanic area in the North Island of New Zealand . It has been active for at least the past two million years and is still highly active. Mount Ruapehu marks its south-western end and
1368-599: Is perhaps best called an embayment. It is associated with the northern fault boundary zone (Rotoehu Fault, Manawahe Fault , North Rotomā Fault, Braemar Fault, Mangaone Fault) in the Whakatāne Graben part of current rift activity in the Taupō Volcanic Zone. The caldera is likely overlying the former drainage valley that historically Lake Rotorua used before the Rotoiti eruption of the Ōkataina Caldera 47,400 ± 1500 years ago. The Rotomā volcano's most prominent feature Lake Rotomā
1440-482: Is rich in silicon , potassium , and sodium and created the ignimbrite sheets of the North Island Volcanic Plateau . The detailed composition suggests subduction erosion might play a predominant role in producing this rhyolite, as later assimilation and fractional crystallization of primary basalt magma, is difficult to model to explain the composition and volumes erupted. This central zone has had
1512-511: Is the relatively sudden appearance of the hotspot in the geologic record. Additionally, the Columbia Basalt flows appeared at the same approximate time in the same place, prompting speculation that they share a common origin. As the Yellowstone hotspot traveled to the east and north, the Columbia disturbance moved northward and eventually subsided. An alternate theory to the mantle plume model
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#17328977288281584-451: Is widening east–west at the rate of about 8 mm (0.31 in)/year, while at Mount Ruapehu it is only 2–4 mm (0.079–0.157 in)/year and this increases at the north eastern end at the Bay of Plenty coast to 10–15 mm (0.39–0.59 in)/year. The rift has had three active stages of faulting in the last 2 million years with the modern Taupō rift evolving in the last 25,000 years after
1656-575: The 1980 Mount St. Helens eruption . The next biggest supereruption formed the Yellowstone Caldera (640,000 years ago) and produced the Lava Creek Tuff . The Henry's Fork Caldera (1.2 million years ago) produced the smaller Mesa Falls Tuff , but is the only caldera from the Snake River Plain–Yellowstone hotspot that is plainly visible today. Non-explosive eruptions of lava and less-violent explosive eruptions have occurred in and near
1728-470: The Hatepe eruption , occurred in 232 CE. It is believed to have first emptied the lake, then followed that feat with a pyroclastic flow that covered about 20,000 km (7,700 sq mi) of land with volcanic ash . A total of 120 km (29 cu mi) of material expressed as dense-rock equivalent (DRE) is believed to have been ejected, and over 30 km (7.2 cu mi) of material
1800-520: The Horomatangi Reefs or Motutaiko Island in Lake Taupō or the lava dome of Mount Tarawera . This later as part of the Ōkataina caldera complex is the highest risk volcanic field in New Zealand to man. Mount Tauhara adjacent to Lake Taupō is actually a dacitic dome and so intermediate in composition between andesite and rhyolite but still more viscous than basalt which is rarely found in
1872-522: The International Union of Geological Sciences (IUGS) included "The Yellowstone volcanic and hydrothermal system" in its assemblage of 100 geological heritage sites around the world in a listing published in October 2022. The organization defines an IUGS Geological Heritage Site as "a key place with geological elements and/or processes of international scientific relevance, used as a reference, and/or with
1944-639: The Taupō Fault Belt , but many faults will be uncharacterised as was the case with the 1987 Edgecumbe earthquake . Earthquakes can be associated with landslides and inland or coastal tsunami that can result in great loss of life and both have happened on the Waihi Fault Zone . The relative low grade volcanic activity of the andesite volcanoes at each end of the zone has resulted in recorded history in both direct loss of life and disrupted transport and tourism. The only high grade eruption in recorded history
2016-472: The Taupō Volcano and the Ōkataina Caldera have had multiple eruptions in the last 25,000 years. The zone's largest eruption since the arrival of Europeans was that of Mount Tarawera (within the Ōkataina Caldera) in 1886, which killed over 100 people. Early Māori would also have been affected by the much larger Kaharoa eruption from Tarawera around 1315 CE. The last major eruption from Lake Taupō,
2088-468: The mantle rises toward the surface. The hotspot appears to move across terrain in the east-northeast direction, and is responsible for the eastern half of Idaho 's Snake River Plain , but in fact the hotspot is much deeper than the surrounding terrain and remains stationary while the North American plate moves west-southwest over it. Over the past 16.5 million years or so, this hotspot has generated
2160-571: The Bay of Plenty coast, the least at Mount Ruapehu and a rate of about 8 mm (0.31 in) per year at Taupō. The zone is named after Lake Taupō , the flooded caldera of the largest volcano in the zone, the Taupō Volcano and contains a large central volcanic plateau as well as other landforms. There are numerous volcanic vents and geothermal fields in the zone, with Mount Ruapehu , Mount Ngauruhoe and Whakaari / White Island erupting most frequently. Whakaari has been in continuous activity since 1826 if you count such as steaming fumaroles, but
2232-506: The Ruapehu and Tongariro grabens . The recent deposits from major eruptions and lake features mean many potentially significant faults are uncharacterised, either completely (for example the 6.5 MW 1987 Edgecumbe earthquake resulted in the mapping of the Edgecumbe fault for the first time) or frequency of events and their likely magnitude are not understood. It can not be assumed that just because
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2304-477: The West Thumb of Yellowstone Lake 174,000 years ago. The three supereruptions occurred 2.1 million, 1.3 million, and approximately 640,000 years ago, forming the Island Park Caldera , the Henry's Fork Caldera , and Yellowstone calderas, respectively. The Island Park Caldera supereruption (2.1 million years ago), which produced the Huckleberry Ridge Tuff , was the largest, and produced 2,500 times as much ash as
2376-473: The Whakamaru eruption the central part of the zone has dominated, so that when the whole zone is considered there has been about 3,000 km (720 cu mi) of rhyolite, 300 km (72 cu mi) of andesite, 20 km (4.8 cu mi) of dacite and 5 km (1.2 cu mi) of basalt erupted. Less gaseous rhyolite magma dome building effusive eruptions have built features such as
2448-569: The Yellowstone Caldera and the Lava Creek Tuff ). The caldera was the largest known until the discovery of Apolaki Caldera in 2019, which is more than twice as wide. Volcanism at Yellowstone is relatively recent, with calderas created by large eruptions that took place 2.1 million, 1.3 million, and 640,000 years ago. The calderas lie over the Yellowstone hotspot under the Yellowstone Plateau where light and hot magma (molten rock) from
2520-439: The Yellowstone caldera since the last supereruption. The most recent lava flow occurred about 70,000 years ago, while a violent eruption excavated the West Thumb of Lake Yellowstone 174,000 years ago. Smaller steam explosions occur as well. An explosion 13,800 years ago left a 5 km (3.1 mi) diameter crater at Mary Bay on the edge of Yellowstone Lake (located in the center of the caldera). Currently, volcanic activity
2592-881: The Yellowstone hotspot. Progressively younger volcanic units, most grouped in several overlapping volcanic fields , extend from the Nevada – Oregon border through the eastern Snake River Plain and terminate in the Yellowstone Plateau. One such field, the Bruneau-Jarbidge volcanic field in southern Idaho , was formed between 10 and 12 million years ago, and the event dropped ash to a depth of one foot (30 cm) 1,000 miles (1,600 km) away in northeastern Nebraska and killed large herds of rhinoceroses , camels, and other animals at Ashfall Fossil Beds State Historical Park. The United States Geological Survey (USGS) estimates there are one or two major caldera-forming eruptions and
2664-564: The central 50 km (12 cu mi) Pokai eruption of about 275 ka, and the paired Mamaku to the north and east central Ohakuri eruptions of about 240,000 years ago that together produced more than 245 km (59 cu mi) dense-rock equivalent of material. The southern Taupō Volcano Oruanui eruption about 25,600 years ago produced 530 km (130 cu mi) dense-rock equivalent of material and its recent Hatepe eruption of 232 CE ± 10 years had 120 km (29 cu mi) dense-rock equivalent. Since
2736-422: The distinctive Waiteariki ignimbrite that erupted 2.1 million years ago in a supereruption, presumably from the gravity anomaly defined Omanawa Caldera , is within the postulated borders of the old Taupō Rift. The multiple intra-rift faults are some of the most active in the country and some have the potential to create over magnitude 7 events. The fault structures are perhaps most well characterised related to
2808-501: The emptied magma chamber , forming a geographic depression called a caldera. The oldest identified caldera remnant straddles the border near McDermitt, Nevada–Oregon , although there are volcaniclastic piles and arcuate faults that define caldera complexes more than 60 km (37 mi) in diameter in the Carmacks Group of southwest-central Yukon , Canada, which are interpreted to have been formed 70 million years ago by
2880-490: The foreseeable future. Recurrence intervals of these events are neither regular nor predictable." This conclusion was reiterated in December 2013 in the aftermath of the publication of a study by University of Utah scientists finding that the "size of the magma body beneath Yellowstone is significantly larger than had been thought". The Yellowstone Volcano Observatory issued a statement on its website stating: Although fascinating,
2952-541: The hydrothermal explosion that formed Mary Bay. Further research shows that very distant earthquakes reach and have effects upon the activities at Yellowstone, such as the 1992 7.3 magnitude Landers earthquake in California 's Mojave Desert that triggered a swarm of quakes from more than 800 miles (1,300 km) away, and the 2002 7.9 magnitude Denali fault earthquake 2,000 miles (3,200 km) away in Alaska that altered
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3024-451: The immense pressure under which the magma is contained. If the pressure is released to a sufficient degree by some geological shift, then some of the gases bubble out and cause the magma to expand. This can cause a chain reaction. If the expansion results in further relief of pressure, for example, by blowing crust material off the top of the chamber, the result is a very large gas explosion. According to analysis of earthquake data in 2013,
3096-591: The intra-arc Taupō Rift. As there is presently no absolute consensus with regard to the cause of the Taupō Rift's extension or its exceptional current volcanic productivity, some of the discussion on this page has been simplified, rather than all possible models being presented. Recent scientific work indicates that the Earth's crust below the Taupō Volcanic Zone may be as little as 16 kilometres thick. A film of magma 50 kilometres (30 mi) wide and 160 kilometres (100 mi) long lies 10 kilometres under
3168-649: The land surface within the caldera moved upward as much as 8 inches (20 cm) at the White Lake GPS station. In January 2010, the USGS stated that "uplift of the Yellowstone Caldera has slowed significantly" and that uplift continues but at a slower pace. USGS, University of Utah and National Park Service scientists with the Yellowstone Volcano Observatory maintain that they "see no evidence that another such cataclysmic eruption will occur at Yellowstone in
3240-413: The largest number of very large silicic caldera-forming eruptions recently on earth as mentioned earlier. During a period of less than 100,000 years commencing with the massive Whakamaru eruption about 335,000 years ago of greater than 2,000 km (480 cu mi) dense-rock equivalent of material, just to the north of the present Lake Taupō , over 4,000 km (960 cu mi) total
3312-459: The last 1000 years. It is formed from rhyolite magma. It has a quite complex eruptive history but only with one definite significant Plinian eruption . Mount Taranaki is an andesite cone and the most recent of four Taranaki volcanoes about 140 km (87 mi) west of the Taupō Volcanic Zone. Associated with the Taupō volcanic zone, intra-arc extension is expressed as normal faulting within
3384-558: The magma chamber in two large influxes. An analysis of crystals from Yellowstone's lava showed that prior to the last supereruption, the magma chamber underwent a rapid increase in temperature and change in composition. The analysis indicated that Yellowstone's magma reservoir can reach eruptive capacity and trigger a super-eruption within just decades, not centuries as volcanologists had originally thought. In respect of it being "well-known for its past explosive volcanic eruptions and lava flows as well for its world class hydrothermal system",
3456-525: The magma chamber is 80 km (50 mi) long and 20 km (12 mi) wide. It also has 4,000 km (960 cu mi) underground volume, of which 6–8% is filled with molten rock. This is about 2.5 times bigger than scientists had previously imagined; however, scientists believe that the proportion of molten rock in the chamber is too low to allow for another supereruption. In October 2017, research from Arizona State University indicated prior to Yellowstone's last supereruption, magma surged into
3528-414: The massive Oruanui eruption and now being within two essentially inactive rift systems. These are the surrounding limits of the young Taupō Rift between 25,000 and 350,000 years and old Taupō Rift system whose northern boundary is now located well to the north of the other two being created before 350,000 years ago. The Tauranga Volcanic Centre which was active between 2.95 to 1.9 million years ago, and
3600-575: The modern Taupō Volcanic Zone in what proved to be an evolving classification scheme: Rotorua, Ōkataina, Maroa, Taupō, Tongariro and Mangakino. The old zone almost certainly contains volcanoes in the Tauranga Volcanic Centre . Other important features of the TVZ include the Ngakuru and Ruapehu grabens . There is more recent, somewhat different classification, by some of the same authors, that uses
3672-690: The new findings do not imply increased geologic hazards at Yellowstone, and certainly do not increase the chances of a 'supereruption' in the near future. Contrary to some media reports, Yellowstone is not 'overdue' for a supereruption. Media reports were more hyperbolic in their coverage. A study published in GSA Today , the monthly news and science magazine of the Geological Society of America , identified three fault zones where future eruptions are most likely to be centered. Two of those areas are associated with lava flows aged 174,000–70,000 years ago, and
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#17328977288283744-479: The past 14,000 years, resulting in such features as Mary Bay, Turbid Lake , and Indian Pond, which was created in an eruption about 1300 BC. In a 2003 report, USGS researchers proposed that an earthquake may have displaced more than 77 million cubic feet (2,200,000 m ; 580,000,000 US gal) of water in Yellowstone Lake, creating colossal waves that unsealed a capped geothermal system and led to
3816-595: The plate boundary changes to a transform boundary with oblique continental collision uplifting the Southern Alps in the South Island . A subduction zone reappears south-west of Fiordland , at the south-western corner of the South Island, although here the subduction is in the opposite direction. Solander Island / Hautere is an extinct volcano associated with this subduction zone, and the only one that protrudes above
3888-450: The rate of expansion of the rift is greatest near the coast that this is where most significant tectonic earthquakes in terms of human risk will be. The Waihi Fault Zone south of Lake Taupō and associated with the Tongariro graben has a particular risk of inducing massive landslips which has caused significant loss of life and appears to be more active than many other faults in the zone. The north ( Whakatane Graben – Bay of Plenty) part of
3960-463: The same applies to say the Okataina volcanic centre . The Taupō Volcanic Zone has produced in the last 350,000 years over 3,900 cubic kilometres (940 cu mi) material, more than anywhere else on Earth, from over 300 silicic eruptions, with 12 of these eruptions being caldera-forming. Detailed stratigraphy in the zone is only available from the Ōkataina Rotoiti eruption but including this event,
4032-560: The sea. In the North Island rifting associated with plate tectonics has defined a Central Volcanic Region, that has been active for four million years and this extends westward from the Taupō volcanic zone through the western Bay of Plenty to the eastern side of the Coromandel Peninsula . The dominant rifting axis associated with the Central Volcanic Region has moved with time, from the back-arc associated Hauraki Rift to
4104-472: The surface. The geological record indicates that some of the volcanoes in the area erupt infrequently but have large, violent and destructive eruptions when they do. Technically the zone is in the continental intraarc Taupō Rift, which is a continuation of oceanic plate structures associated with oblique Australian and Pacific Plate convergence in the Hikurangi subduction zone . At Taupō the rift volcanic zone
4176-632: The term caldera complex: Yellowstone Caldera The Yellowstone Caldera , sometimes referred to as the Yellowstone Supervolcano , is a volcanic caldera and supervolcano in Yellowstone National Park in the Western United States . The caldera and most of the park are located in the northwest corner of the state of Wyoming . The caldera measures 43 by 28 miles (70 by 45 kilometers), and postcaldera lavas spill out
4248-415: The third is a focus of present-day seismicity . In 2017, NASA conducted a study to determine the feasibility of preventing the volcano from erupting. The results suggested that cooling the magma chamber by 35 percent would be enough to forestall such an incident. NASA proposed introducing water at high pressure 10 kilometers underground. The circulating water would release heat at the surface, possibly in
4320-724: The timescale of likely warning of such an event. These eruptions are associated with tephra production that results in deep ash fall over wide areas (e.g. the Whakatane eruption of ~ 5500 years ago had 5 mm (0.20 in) ashfall 900 km (560 mi) away on the Chatham Islands ) ` pyroclastic flows and surges, which rarely have covered large areas of the North Island in ignimbrite sheets, earthquakes, lake tsunamis, prolonged lava dome growth and associated block and ash flows with post-eruption lahars and flooding. Download coordinates as: The following Volcanic Centres belong to
4392-458: The zone has been more productive than any other rhyolite predominant volcanic area over the last 50,000 odd years at 12.8 km (3.1 cu mi) per thousand years. Comparison of large events in the Taupō volcanic zone over the last 1.6 million years at 3.8 km (0.91 cu mi) per thousand years with Yellowstone Caldera 's 2.1 million year productivity at 3.0 km (0.72 cu mi) per thousand years favours Taupo. Both
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#17328977288284464-405: The zone is predominantly formed from andesitic magma and represented by the continuously active Whakaari / White Island andesite – dacite stratovolcano. Although Strombolian activity has occurred the explosive eruptions are typically phreatic or phreatomagmatic . The active emergent summit tops the larger, 16 kilometres (9.9 mi) × 18 kilometres (11 mi), submarine volcano with
4536-511: The zone runs north-eastward through the Taupō and Rotorua areas and offshore into the Bay of Plenty . It is part of a larger Central Volcanic Region that extends to the Coromandel Peninsula and has been active for four million years. The zone is contained within the tectonic intra-arc continental Taupō Rift and this rift volcanic zone is widening unevenly east–west, with the greatest rate of widening at
4608-419: The zone. The southern part of the zone contain classic volcanic cone structure formed from andesite magma in effusive eruptions that cool to form dark grey lava if gas-poor or scoria if gas-rich of this part of the zone. Mount Ruapehu, the tallest mountain in the North Island, is a 150 km (36 cu mi) andesite cone surrounded by a 150 km (36 cu mi) ring-plain. This ring plain
4680-544: Was Earth's most recent eruption reaching VEI-8, the highest level on the Volcanic Explosivity Index . The Rotorua caldera has been dormant longer, with its main eruption occurring about 225,000 years ago, although lava dome extrusion has occurred within the last 25,000 years. The Taupō volcanic zone is approximately 350 kilometres (217 mi) long by 50 kilometres (31 mi) wide. Mount Ruapehu marks its southwestern end, while Whakaari / White Island
4752-517: Was Yellowstone's third and most recent caldera-forming eruption. Geologists closely monitor the elevation of the Yellowstone Plateau , which has been rising as quickly as 150 millimetres (5.9 in) per year, as an indirect measurement of changes in magma chamber pressure. The upward movement of the Yellowstone caldera floor between 2004 and 2008—almost 75 millimetres (3.0 in) each year—was more than three times greater than ever observed since such measurements began in 1923. From 2004 to 2008,
4824-425: Was atypically basaltic from Mount Tarawera and although very destructive is not likely to be a perfect model for the more typical and often larger rhyolitic events associated with the Taupō Volcano and the Ōkataina Caldera . As mentioned earlier the Ōkataina caldera complex is the highest risk volcanic field risk in New Zealand to man and the recent frequency of rhyolitic events there is not reassuring, along with
4896-495: Was erupted. These eruptions essentially defined the limits of the present central volcanic plateau , although its current central landscape is mainly a product of later smaller events over the last 200,000 years than the Whakamaru eruption. The other volcanic plateau defining eruptions were to the west, the 150 km (36 cu mi) Matahina eruption of about 280,000 years ago, the mainly tephra 50 km (12 cu mi) Chimp (Chimpanzee) eruption between 320 and 275 ka,
4968-517: Was formed within the Rotomā caldera when lava flows following a large crater explosion blocked its outlet. The major eruption episodes were about 7412 BCE with about 8 km (1.9 cu mi) of material erupted from 3 different magmas from several different vents. This eruptive sequence was associated in time with ruptures in the Manawahe Fault about 10 km (6.2 mi) to the north-east. It
5040-419: Was previously classified as part of the Central Volcanic Region, appears now to be in a tectonic continuum with the Taupō Volcanic Zone. Recent ocean floor tephra studies off the east coast of the North Island have shown an abrupt compositional change in these, from about 4.5 million years ago, that has been suggested to distinguish Coromandel Volcanic Zone activity from that of the Taupō Volcanic Zone. Further
5112-512: Was proposed in 2018. It is suggested that the volcanism may be caused by upwellings from the lower mantle resulting from water-rich fragments of the Farallon plate descending from the Cascadia subduction region , sheared off at a subducted spreading rift. Others suggest that the mantle plume could not have been a dominant force in Yellowstone volcanism due to the sinking Farallon plate, as it acts as
5184-472: Was the cause of the tsunami tens of metres tall that went up to 7 kilometres (4.3 mi) inland in the Bay of Plenty at about this time. Although significant tsunami's can be associated with volcanic eruptions, it is unknown if the cause was a relatively small eruption of Whakaari or another cause such as a large local earthquake Taupō erupted an estimated 1,170 km (280 cu mi) of DRE material in its Oruanui eruption 25,580 years ago. This
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