Lake Taupō Lake Taupō (also spelled Taupo; mi, Taupō-nui-a-Tia or ) is a large crater lake in New Zealand's North Island, located in the caldera of the Taupō Volcano. The lake is the namesake of the town of Taupō, which sits on a bay in the lake's n ...

, in the centre 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 smaller islands. It is the sixth-largest island coun ...

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 ...

, is the

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is ...

of the Taupō Volcano, a large

rhyolitic Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals ( phenocrysts) in an otherwise fine-grained groundmass. The ...

supervolcano A supervolcano is a volcano that has had an eruption with a Volcanic Explosivity Index (VEI) of 8, the largest recorded value on the index. This means the volume of deposits for such an eruption is greater than 1,000 cubic kilometers (240 cubi ...

. This huge

volcano A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates ...

has produced two of the world's most violent eruptions in geologically recent times.

ImageSize = width:320 height:800 PlotArea = right:50 top:10 left:50 bottom:10 DateFormat = yyyy TimeAxis = orientation:vertical order:reverse Period = from:-10000 till:2050 AlignBars = early ScaleMajor = unit:year increment:1000 start:-10000 Colors = id:canvas value:rgb(1,1,0.85) BackgroundColors = canvas:canvas PlotData = width:15 color:white bar:test from:-10000 till:1200 # Pre Maori PlotData = width:15 color:yellow bar:test from:1200 till:1840 # Pre accurate PlotData = width:15 color:orange bar:test from:1840 till:2050 # Accurate PlotData = at:-9999 shift:(30,0) text: Recent eruptions of Taupō caldera at:-9999 shift:(200,0) textcolor:red text: Eruptive at:-9850 shift:(80,-1) textcolor:red fontsize:S text:(Eruptive volume) at:-9850 shift:(210,0) textcolor:red text: Index at:-9700 shift:(200,0) textcolor:red text: 6 5 4 3 2 1 at:-9460 shift:(10,-5) text: 9460 BCE East/Central Unit B at:-9460 shift:(217,2) textcolor:red fontsize:S text:(0.5 km ) at:-9460 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-9460 mark:(line,red) at:-9240 shift:(10,-2) text: 9240 BCE Te Kohaiakatu Pt Unit C at:-9240 shift:(217,2) textcolor:red fontsize:S text:(0.3 km ) at:-9240 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-9240 mark:(line,red) at:-9210 shift:(10,-10) text: 9210 BCE at:-9210 shift:(63,-10) text: Acacia Bay Unit D at:-9210 shift:(147,-10) textcolor:red fontsize:S text:(0.1 km ) at:-9210 shift:(183,-8) textcolor:red fontsize:XS text:3 bar:test at:-9210 mark:(line,red) at:-8130 shift:(10,-5) text: 8130 BCE East/Central Unit E at:-8130 shift:(226,2) textcolor:red fontsize:S text:(2 km ) at:-8130 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-8130 mark:(line,red) at:-5100 shift:(10,-5) text: 5100 BCE at:-5100 shift:(63,-5) text:

Motutaiko Island Motuaiko Island is the only island within Lake Taupō on the North Island of New Zealand. It sits near the town of Motutere. The name "Motutaiko" is from the Māori language, with "motu" meaning island, and "taiko" being a name for the black ...

Unit F at:-5100 shift:(212,2) textcolor:red fontsize:S text:(0.07 km ) at:-5100 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-5100 mark:(line,red) at:-4700 shift:(10,-5) text: 4700 BCE East/Central Unit G at:-4700 shift:(217,2) textcolor:red fontsize:S text:(0.2 km ) at:-4700 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-4700 mark:(line,red) at:-4100 shift:(10,-5) text: 4100 BCE Te Kohaiakatu Pt Unit H at:-4100 shift:(212,2) textcolor:red fontsize:S text:(0.08 km ) at:-4100 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-4100 mark:(line,red) at:-4000 shift:(10,-8) text: 4000 BCE Unit I at:-4000 shift:(87,-8) textcolor:red fontsize:S text:(0.02 km ) at:-4000 shift:(128,-6) textcolor:red fontsize:XS text:3 bar:test at:-4000 mark:(line,red) at:-3420 shift:(10,0) text: 3420 BCE Unit J at:-3420 shift:(207,2) textcolor:red fontsize:S text:(0.015 km ) at:-3420 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-3420 mark:(line,red) at:-3170 shift:(10,7) text: 3170 BCE Te Kohaiakatu Pt Unit K at:-3170 shift:(212,6) textcolor:red fontsize:S text:(0.35 km ) at:-3170 shift:(253,8) textcolor:red fontsize:XS text:3 bar:test at:-3170 mark:(line,red) at:-3120 shift:(10,1) text: 3120 BCE Te Kohaiakatu Pt Unit L at:-3120 shift:(171,1) textcolor:red fontsize:S text:(0.07 km ) at:-3120 shift:(212,3) textcolor:red fontsize:XS text:3 bar:test at:-3120 mark:(line,red) at:-3070 shift:(10,-5) text: 3070 BCE Te Kohaiakatu Pt Unit M at:-3070 shift:(176,-5) textcolor:red fontsize:S text:(0.2 km ) at:-3070 shift:(212,-3) textcolor:red fontsize:XS text:3 bar:test at:-3070 mark:(line,red) at:-2900 shift:(10,-3) text: 2900 BCE Te Kohaiakatu Pt Unit N at:-2900 shift:(174,-3) textcolor:red fontsize:S text:(0.15 km ) at:-2900 shift:(215,-1) textcolor:red fontsize:XS text:3 bar:test at:-2900 mark:(line,red) at:-2850 shift:(10,-9) text: 2850 BCE Te Tuhi Pt Unit O at:-2850 shift:(143,-9) textcolor:red fontsize:S text:(0.05 km ) at:-2850 shift:(184,-7) textcolor:red fontsize:XS text:3 bar:test at:-2850 mark:(line,red) at:-2800 shift:(10,-15) text: 2800 BCE Unit P at:-2800 shift:(93,-15) textcolor:red fontsize:S text:(0.05 km ) at:-2800 shift:(134,-13) textcolor:red fontsize:XS text:3 bar:test at:-2800 mark:(line,red) at:-2600 shift:(10,-11) text: 2600 BCE Te Kohaiakatu Pt Unit Q at:-2600 shift:(212,2) textcolor:red fontsize:S text:(0.15 km ) at:-2600 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-2600 mark:(line,red) at:-2500 shift:(10,-14) text: 2500 BCE at:-2500 shift:(63,-14) text:

Unit R at:-2500 shift:(173,-14) textcolor:red fontsize:S text:(0.05 km ) at:-2500 shift:(214,-12) textcolor:red fontsize:XS text:3 bar:test at:-2500 mark:(line,red) at:-1460 shift:(10,-5) text: 1460 BCE at:-1460 shift:(63,-5) text: Horomatangi Reefs Unit S at:-1460 shift:(217,2) textcolor:red fontsize:S text:(7.5 km ) at:-1460 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-1460 mark:(line,red) at:-1250 shift:(10,-5) text: 1250 BCE Te Kohaiakatu Pt Unit T at:-1250 shift:(212,2) textcolor:red fontsize:S text:(0.05 km ) at:-1250 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-1250 mark:(line,red) at:-1050 shift:(10,-3) text: 1050 BCE at:-1050 shift:(63,-3) text:

Unit U at:-1050 shift:(217,2) textcolor:red fontsize:S text:(0.1 km ) at:-1050 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-1050 mark:(line,red) at:-1010 shift:(10,-11) text: 1010 BCE Te Kohaiakatu Pt Unit V at:-1010 shift:(174,-11) textcolor:red fontsize:S text:(0.4 km ) at:-1010 shift:(210,-9) textcolor:red fontsize:XS text:3 bar:test at:-1010 mark:(line,red) at:-800 shift:(10,-7) text: 800 BCE Ouaha Hills Unit W at:-800 shift:(146,-7) textcolor:red fontsize:S text:(0.023 km ) at:-800 shift:(193,-5) textcolor:red fontsize:XS text:3 bar:test at:-800 mark:(line,red) at:-200 shift:(10,-5) text: 200 BCE Te Kohaiakatu Pt Unit X at:-200 shift:(212,2) textcolor:red fontsize:S text:(0.28 km ) at:-200 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:-200 mark:(line,red) at:233 shift:(33,0) text:

Hatepe eruption The Hatepe eruption, named for the Hatepe Plinian pumice tephra layer, sometimes referred to as the Taupō eruption or Horomatangi Reef Unit Y eruption, is dated to 232 CE ± 10 and was Taupō Volcano's most recent major eruption. It is tho ...

Unit Y at:233 shift:(10,0) text: 233 at:233 shift:(214,2) textcolor:red fontsize:S text:(120 km ) at:233 shift:(253,4) textcolor:red fontsize:XS text:3 bar:test at:233 mark:(line,red) at:260 shift:(10,-10) text: 260 at:260 shift:(33,-10) text: Horomatangi Reef area at:260 shift:(142,-10) textcolor:red fontsize:S text:(volume unknown) bar:test at:260 mark:(line,red) at:1200 shift:(10,-5) text: Māori in NZ bar:test at:1200 mark:(line,black) at:1840 shift:(10,-5) text: European colonisation bar:test at:1840 mark:(line,black) LineData = at:260 frompos:315 tillpos:320 color:red width:2 at:233 frompos:260 tillpos:320 color:red width:2 at:-200 frompos:280 tillpos:320 color:red width:2 at:-800 frompos:300 tillpos:320 color:red width:2 at:-1010 frompos:280 tillpos:320 color:red width:2 at:-1050 frompos:280 tillpos:320 color:red width:2 at:-1250 frompos:290 tillpos:320 color:red width:2 at:-1460 frompos:270 tillpos:320 color:red width:2 at:-2500 frompos:290 tillpos:320 color:red width:2 at:-2600 frompos:280 tillpos:320 color:red width:2 at:-2800 frompos:290 tillpos:320 color:red width:2 at:-2850 frompos:290 tillpos:320 color:red width:2 at:-2900 frompos:280 tillpos:320 color:red width:2 at:-3070 frompos:280 tillpos:320 color:red width:2 at:-3120 frompos:290 tillpos:320 color:red width:2 at:-3170 frompos:280 tillpos:320 color:red width:2 at:-3420 frompos:290 tillpos:320 color:red width:2 at:-4000 frompos:290 tillpos:320 color:red width:2 at:-4100 frompos:280 tillpos:320 color:red width:2 at:-4700 frompos:280 tillpos:320 color:red width:2 at:-5100 frompos:290 tillpos:320 color:red width:2 at:-8130 frompos:270 tillpos:320 color:red width:2 at:-9210 frompos:280 tillpos:320 color:red width:2 at:-9240 frompos:270 tillpos:320 color:red width:2 at:-9460 frompos:270 tillpos:320 color:red width:2

The volcano is in the

Taupō Volcanic Zone The Taupō Volcanic Zone (TVZ) is a volcanic area in the North Island of New Zealand that has been active for the past two million years and is still highly active. Mount Ruapehu marks its south-western end and the zone runs north-eastward throu ...

, a region of

rift In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-grabe ...

volcanic activity that extends from Ruapehu in the south, through the

Taupō Taupō (), sometimes written Taupo, is a town on the north-eastern shore of Lake Taupō, New Zealand's largest lake, in the central North Island. It is the largest urban area of the Taupō District, and the second-largest urban area in the Wa ...

and

Rotorua Rotorua () is a city in the Bay of Plenty region of New Zealand's North Island. The city lies on the southern shores of Lake Rotorua, from which it takes its name. It is the seat of the Rotorua Lakes District, a territorial authority encomp ...

districts, to

Whakaari/White Island Whakaari / White Island (, mi, Te Puia Whakaari, lit. "the dramatic volcano"), also known as White Island or Whakaari, is an active andesite stratovolcano situated from the east coast of the North Island of New Zealand, in the Bay of Plent ...

, in the

Bay of Plenty The Bay of Plenty ( mi, Te Moana-a-Toi) is a region of New Zealand, situated around a bight of the same name in the northern coast of the North Island. The bight stretches 260 km from the Coromandel Peninsula in the west to Cape Runaw ...

. Taupō began erupting about 300,000 years ago. The main eruptions that still affect the surrounding landscape are the

dacitic Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyol ...

Mount Tauhara Mount Tauhara is a dormant lava dome volcano in New Zealand's North Island, reaching above sea level. It is situated in the area of caldera rim overlap of the Whakamaru Caldera and Taupō Volcano towards the centre of the Taupō Volcanic Zone, ...

eruption 65,000 years ago, the

Oruanui eruption The Oruanui eruption of New Zealand's Taupō Volcano (also known as the Kawakawa eruption or Kawakawa/Oruanui event) was the world's most recent supereruption.} Eruption With a Volcanic Explosivity Index of 8, it is one of the largest eruptio ...

about 26,500 years ago, which is responsible for the shape of the modern caldera, and the

, dated 232 ± 10 CE. There have been many more eruptions, with major ones every thousand years or so (see timeline of last 10,000 years of eruptions). Taupō Volcano has not erupted for approximately 1,800 years; however, with research beginning in 1979 and published in 2022, the data collated over the 42-year period shows that Taupō Volcano is active with periods of volcanic unrest and has been for some time. Some volcanoes within the Taupō Volcanic Zone have erupted more recently.

Mount Tarawera Mount Tarawera is a volcano on the North Island of New Zealand within the older but volcanically productive Ōkataina Caldera. Located 24 kilometres southeast of Rotorua, it consists of a series of rhyolitic lava domes that were fiss ...

had a violent VEI-5 eruption in

1886 Events January–March * January 1 – Upper Burma is formally annexed to British Burma, following its conquest in the Third Anglo-Burmese War of November 1885. * January 5– 9 – Robert Louis Stevenson's novella ''Strange ...

, and

is frequently active, erupting most recently in December 2019.

Rhyolitic eruptions

The Taupō Volcano erupts

rhyolite Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals ( phenocrysts) in an otherwise fine-grained groundmass. The miner ...

, a viscous

magma Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natura ...

, with a high

silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is ...

content. If the magma does not contain much gas, rhyolite tends to just form a

lava dome In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions ...

. However, when mixed with gas or

steam Steam is a substance containing water in the gas phase, and sometimes also an aerosol of liquid water droplets, or air. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporizatio ...

, rhyolitic eruptions can be extremely violent. The magma froths to form

pumice Pumice (), called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough-textured volcanic glass, which may or may not contain crystals. It is typically light-colored. Scoria is another vesicular v ...

and

ash Ash or ashes are the solid remnants of fires. Specifically, ''ash'' refers to all non-aqueous, non-gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash ...

, which is thrown out with great force. If the volcano creates a stable plume, high in the

atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A ...

, the pumice and ash are blown sideways, and eventually fall to the ground, draping the landscape like snow. If the material thrown out cools more rapidly and becomes denser than the air, it cannot rise as high, and suddenly collapses back to the ground, forming a

pyroclastic flow A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of b ...

, hitting the surface like water from a waterfall, and spreading sideways across the land at enormous speed. When the pumice and ash settle, they are sufficiently hot to stick together as a rock called

ignimbrite Ignimbrite is a type of volcanic rock, consisting of hardened tuff. Ignimbrites form from the deposits of pyroclastic flows, which are a hot suspension of particles and gases flowing rapidly from a volcano, driven by being denser than the surro ...

. Pyroclastic flows can travel hundreds of kilometres an hour.

Earlier eruptions

Earlier ignimbrite eruptions occurred further north than Taupō. Some of these were enormous, and two eruptions around 1.25 and 1.0 million years ago were big enough to generate an ignimbrite sheet that covered the North Island from

Auckland Auckland (pronounced ) ( mi, Tāmaki Makaurau) is a large metropolitan city in the North Island of New Zealand. The most populous urban area in the country and the fifth largest city in Oceania, Auckland has an urban population of about I ...

to Napier. While Taupō has been active for 300,000 years, explosive eruptions became more common 65,000 years ago.

Oruanui eruption

The Oruanui eruption of the Taupō Volcano was the world's largest known eruption in the past 70,000 years, with a Volcanic Explosivity Index of 8. It occurred around 26,500 years ago and generated approximately of

pyroclastic fall A pyroclastic fall is a uniform deposit of material which has been ejected from a volcanic eruption or plume such as an ash fall or tuff. Pyroclastic air fall deposits are a result of: # Ballistic transport of ejecta such as volcanic blocks, vol ...

deposits, of pyroclastic density current (PDC) deposits (mostly

) and of primary intracaldera material, equivalent to of

. Modern

partly fills the

generated during this eruption.

Tephra Tephra is fragmental material produced by a volcanic eruption regardless of composition, fragment size, or emplacement mechanism. Volcanologists also refer to airborne fragments as pyroclasts. Once clasts have fallen to the ground, they r ...

from the eruption covered much of the central

with ignimbrite up to deep. The ignimbrite eruption(s) were possibly not as forceful as that of the later

but the total impact of this eruption was somewhat greater. Most of New Zealand was affected by ashfall, with an ash layer left even on the

Chatham Islands The Chatham Islands ( ) (Moriori: ''Rēkohu'', 'Misty Sun'; mi, Wharekauri) are an archipelago in the Pacific Ocean about east of New Zealand's South Island. They are administered as part of New Zealand. The archipelago consists of about t ...

, away. Later

erosion Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is d ...

and

sedimentation Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to the ...

had long-lasting effects on the landscape, and caused the

Waikato River The Waikato River is the longest river in New Zealand, running for through the North Island. It rises on the eastern slopes of Mount Ruapehu, joining the Tongariro River system and flowing through Lake Taupō, New Zealand's largest lake. It th ...

to shift from the Hauraki Plains to its current course through the Waikato to the

Tasman Sea The Tasman Sea (Māori: ''Te Tai-o-Rēhua'', ) is a marginal sea of the South Pacific Ocean, situated between Australia and New Zealand. It measures about across and about from north to south. The sea was named after the Dutch explorer ...

Hatepe eruption

The Hatepe eruption (also known as the Taupō or Horomatangi Reef Unit Y eruption) represents the most recent major eruption of the Taupō Volcano, and occurred about 1,800 years ago. It was the most violent eruption in the world in the last 5,000 years.

Stages of eruption

The eruption went through several stages. *A minor eruption occurred beneath the ancestral Lake Taupō. *A dramatic increase in activity produced a high

eruption column An eruption column or eruption plume is a cloud of super-heated ash and tephra suspended in gases emitted during an explosive volcanic eruption. The volcanic materials form a vertical column or plume that may rise many kilometers into the ai ...

from a second vent, and pumice was deposited over a wide area. *Water entered the first vent and mixed with the magma, producing a white ash-rich pumice fall. *A new vent formed and produced a dark ash- and

obsidian Obsidian () is a naturally occurring volcanic glass formed when lava extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock. Obsidian is produced from felsic lava, rich in the lighter elements such as silicon ...

-rich fall deposit. *A larger eruption ensued, producing pumice over a huge area, and a small

deposit. *The most destructive part of the eruption then occurred. Part of the vent area collapsed, unleashing about of material, that formed a fast-moving, pyroclastic flow. *

Rhyolitic Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals ( phenocrysts) in an otherwise fine-grained groundmass. The ...

s were extruded some years later, helping form the Horomatangi

Reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes—deposition of sand, wave erosion planing down rock ...

s and Waitahanui bank. These later smaller eruptions of unknown total size also created large

pumice raft A pumice raft is a floating raft of pumice created by some eruptions of submarine volcanoes or coastal subaerial volcanoes. Biologists suggest that animals and plants have migrated from island to island on pumice rafts. Pumice rafts have uniqu ...

s and terminated within decades of the major eruption. The main pyroclastic flow devastated the surrounding area, climbing over to overtop the nearby Kaimanawa Ranges and

Mount Tongariro Mount Tongariro (; ) is a compound volcano in the Taupō Volcanic Zone of the North Island of New Zealand. It is located to the southwest of Lake Taupō, and is the northernmost of the three active volcanoes that dominate the landscape of th ...

, and covering the land within with

from

to Waiouru. Only Ruapehu was high enough to divert the flow. The power of the pyroclastic flow was so strong that in some places it eroded more material off the ground surface than it replaced with ignimbrite. Valleys were filled with ignimbrite, evening out the shape of the land. All vegetation within the area was flattened. Loose pumice and ash deposits formed

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 extr ...

s down all the main rivers. The eruption further expanded the lake, which had formed after the much larger Oruanui eruption. The previous outlet was blocked, raising the lake above its present level until it broke out in a huge flood, flowing for more than a week at roughly 200 times the

's current rate.

Dating the Hatepe eruption

Many dates have been given for the Hatepe eruption. One estimated date was 181 CE from

ice core An ice core is a core sample that is typically removed from an ice sheet or a high mountain glacier. Since the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper ones, and an ice core contains ...

s in

Greenland Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland ...

and

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest cont ...

. It is possible that the

meteorological Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not ...

phenomena described by Fan Ye in China and by

Herodian Herodian or Herodianus ( el, Ἡρωδιανός) of Syria, sometimes referred to as "Herodian of Antioch" (c. 170 – c. 240), was a minor Roman civil servant who wrote a colourful history in Greek titled ''History of the Empire from the Death o ...

in Rome were due to this eruption, which would give a date of exactly 186. However, ash from volcanic activity does not normally cross hemispheres, and radiocarbon dating by R. Sparks has put the date at 233 CE ± 13 (95% confidence). A 2011 ¹⁴C wiggle-matching paper gave the date 232 ± 5 CE. A 2021 review based on five sources reports 232 ± 10 CE. New Zealand was unpopulated at that time, so the nearest humans would have been in Australia and New Caledonia, more than to the west and northwest.

Current activity and future hazards

From May through December 2022 there was increased

earthquake An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, fr ...

activity with lakeside

slumping Slumping is a technique in which items are made in a kiln by means of shaping glass over molds at high temperatures. The slumping of a pyrometric cone is often used to measure temperature in a kiln. Technique Slumping glass is a highly techni ...

and

inundation A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrolog ...

from a small

tsunami A tsunami ( ; from ja, 津波, lit=harbour wave, ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater exp ...

and ground deformation. The

Volcanic Alert Level In New Zealand, Volcano Alert Bulletins (VABs) are the official source of warnings and alerts including current Volcanic Alert Level (VAL), intended to inform stakeholder agencies, authorities, and the public about emergencies so they can take act ...

for Taupō Volcano was raised to Volcanic Alert Level 1 (minor volcanic unrest) on 20 September 2022. While no witnessed eruptive event has been recorded from Taupō, there have been seventeen episodes of volcanic unrest since 1872, with the most recent being in 2019. This manifested as swarms of seismic activity and ground deformation within the caldera. The present-day magma reservoir is estimated to be at least in volume and have a melt fraction of >20%–30%. The main volcanic hazard at Taupō is from a massive explosive eruption which could create a natural disaster of extreme magnitude given the size of the present magma chamber and that its last eruption was the most severe worldwide in the last 5,000 years. However some of the 29 eruptions of various magnitudes in the last 30,000 years have been much smaller. Many have been dome-forming, which may have contributed to lake features such as

and the Horomatangi Reefs. Earthquake and tsunami hazards also exist. While most earthquakes are relatively small and associated with magma shifts, the moderate earthquakes associated with eruptions or the numerous

-associated faults historically have produced tsunami events. The intra-rift Waihi fault, for example, has been associated with 6.5 magnitude earthquakes at recurrence intervals of between 490 and 1,380 years and at least one tsunami related to

landslip Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated slope failures, mudflows, and debris flows. Landslides occur in a variety of environme ...

at the Hipaua steaming cliffs.

GNS Science GNS Science ( mi, Te Pū Ao), officially registered as the Institute of Geological and Nuclear Sciences Limited, is a New Zealand Crown Research Institute. It focuses on geology, geophysics (including seismology and volcanology), and nuclear sc ...

continuously monitors Taupō using a network of

seismograph A seismometer is an instrument that responds to ground noises and shaking such as caused by earthquakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The outpu ...

s and GPS stations. The Horomatangi Reefs area of the lake is associated with active

hydrothermal vent A hydrothermal vent is a fissure on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hotspo ...

ing and high heat flow. Monitoring of a volcano situated under a lake is challenging, and an eruption might occur with little or no meaningful notice. Live data can be viewed on th
GeoNet website

References

External links

Lake-floor relief map
from . Same data exists in {{Cite journal , last=Rowe , first=Dave , author2=James, Gavin , author3=Macaulay, Gavin , author4=Shankar, Ude , date=October 2002 , url=http://www.niwascience.co.nz/pubs/wa/ma/10-3/tools , title=High-tech tools for tackling fisheries problems in lakes , journal=Water & Atmosphere , volume=10 , issue=3 , pages=24–25 , publisher=

NIWA The National Institute of Water and Atmospheric Research or NIWA ( mi, Taihoro Nukurangi), is a Crown Research Institute of New Zealand. Established in 1992, NIWA conducts research across a broad range of disciplines in the environmental scienc ...

, access-date=16 March 2008 , url-status=dead , archive-url=https://web.archive.org/web/20080502191322/http://www.niwascience.co.nz/pubs/wa/ma/10-3/tools , archive-date=2 May 2008 Holocene calderas Pleistocene calderas Taupō Volcanic Zone Geology of New Zealand Calderas of New Zealand VEI-8 volcanoes VEI-7 volcanoes VEI-6 volcanoes Supervolcanoes Landforms of Waikato Tsunamis in New Zealand Lists of volcanic eruptions Lake Taupō Volcanoes of Waikato