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 through the Taupō and Rotorua areas and offshore into the Bay of Plenty. It is part of the larger Central Volcanic Region that extends further westward through the western Bay of Plenty to the eastern side of the Coromandel Peninsula and has been active for four million years.[1] At Taupō the volcanic zone is widening east–west at the rate of about 8 mm per year while at Mount Ruapehu it is only 2–4 mm per year but this has increases at the north eastern end at the Bay of Plenty coast to 10–15 mm per year.[2] It is named after Lake Taupō, the flooded caldera of the largest volcano in the zone, the Taupō Volcano.

Volcano and lake/caldera locations in the Taupō Volcanic Zone. The distance between the town of Rotorua and the town of Taupō is 80 km. (White Island is not shown.)

Activity

There are numerous volcanic vents and geothermal fields in the zone, with Mount Ruapehu, Mount Ngauruhoe and White Island erupting most frequently. Whakaari has been in continuous activity since 1826 if you count such as steaming fumaroles, but the same applies to say the Okataina volcanic centre.[3] The zone's largest eruption since the arrival of Europeans was that of Mount Tarawera in 1886, which killed over 100 people. Early Maori would also have been affected by the much larger Kaharoa eruption from Tarawera around 1315 CE.[4][5]

The last major eruption from Lake Taupō, the Hatepe eruption, occurred in 232 CE.[6] It is believed to have first emptied the lake then followed that feat with a pyroclastic flow that covered about 20,000 km2 (7,700 sq mi) of land with volcanic ash. A total of 120 km3 (29 cu mi) of material is believed to have been ejected, and over 30 km3 (7.2 cu mi) of material 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.[6]

White Island had a major, edifice failure collapse of its volcano dated to 946 BCE ± 52 years. It has been suggested that this was the cause of the large tsunami that went up to 7 km inland (i.e. tens of meters tall) 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[7]

Taupō erupted an estimated 1,170 km3 (280 cu mi) of material in its Oruanui eruption 25,600 years ago.[8] This 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 240,000 years ago, although lava dome extrusion has occurred within the last 25,000 years.[9]

Mount Ngauruhoe
Satellite photo of the Lake Taupō caldera
Whakaari/White Island

Extent and geological context

The Taupō Volcanic zone is approximately 350 kilometres (217 mi) long by 50 kilometres (31 mi) wide. Mount Ruapehu marks its southwestern end, while White Island is considered its northeastern limit.[10]

It forms a southern portion of the active Lau-Havre-Taupō back-arc basin, which lies behind the Kermadec-Tonga subduction zone.[11][12] Volcanic activity continues to the north-northeast, along the line of the Taupō Volcanic Zone, through several undersea volcanoes (known as Clark, Tangaroa, the Silents and the Rumbles), then shifts eastward to the parallel volcanic arc of the Kermadec Islands and Tonga. Although the back-arc basin continues to propagate to the southwest, with the South Wanganui Basin forming an initial back-arc basin, volcanic activity has not yet begun in this region.[13]

South of Kaikoura the plate boundary changes to a transform boundary with oblique continental collision uplifting the Southern Alps / Kā Tiritiri o te Moana in the South Island. A subduction zone reappears southwest of Fiordland, at the southwestern corner of the South Island, although here the subduction is in the opposite direction. Solander Island is an extinct volcano associated with this subduction zone, and the only one that protrudes above the sea.

Scientific study

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 the surface.[14][15] 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 it is also known as the continental intraarc Taupō rift. This 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 the massive Oruanui eruption, the surrounding young Taupō Rift between 25,000 and 350,000 years and old Taupō Rift system now located to the north of the other two being created between 350,000 and 2 million years.[2]

Volcanoes, lakes and geothermal fields
See also: List of volcanoes in New Zealand § Taupō Volcanic Zone

The following Volcanic Centers belong to the Taupō Volcanic Zone:

Rotorua, Okataina, Maroa, Taupō, Tongariro and Mangakino.[16][17]

In 1886, Mount Tarawera produced New Zealand's largest historic eruption
Lady Knox Geyser, Waiotapu geothermal area
Craters of the Moon geothermal area
Composite satellite image of Mount Ruapehu
Satellite view of the Lake Rotorua Caldera. Mount Tarawera is in the lower right corner.
Southwest side of Mount Tarawera, Mount Edgecumbe on the background.

        Other important features of the TVZ include the Whakatane, Ngakuru and Ruapehu grabens.

Note


There is nowadays a somewhat different classification:[24][25]

  • North part: Whakatane Graben – Bay of Plenty
  • Central part:
    • West of the main fault zone:
      • Mangakino caldera complex; may be transitional between Coromandel Volcanic Zone (CVZ) and Taupō Volcanic Zone (TVZ) (1.62 – 0.91 mio. years old)
      • Kapenga caldera; lies between the Maroa caldera and the Rotorua caldera, it is completely buried under more recent tephra (circa 700,000 years old)
        • Okareka Embayment, lies inside the northern end of the Kapenga Caldera, between the Tarawera volcanic complex and the Lake Rotorua[22]
      • Rotorua single event caldera; Mamaku Ignimbrite (circa 240,000 years old)
    • Main fault zone:
      • Okataina caldera complex
        • Haroharo caldera complex
          • Tarawera volcanic complex
          • Okareka Embayment
      • Whakamaru caldera complex
        • Maroa caldera
      • Ohakuri single event caldera; Ohakuri Ignimbrite; lies West of the Ohakuri Dam, the Waikato River course follows roughly the southern caldera rim on one side (circa 240,000 years old).[26]
      • Taupō caldera complex
    • East of the main fault zone:
      • Reporoa single event caldera; Kaingaroa Ignimbrite (circa 240,000 years old)
  • South part: Tongariro Volcanic Centre
Panorama across Lake Taupō

See also

References
  1. Cole, J.W.; Darby, D.J.; Stern, T.A. (1995). "Taupo Volcanic Zone and Central Volcanic Region: Backarc Structures of North Island, New Zealand". In Taylor, Brian (ed.). Backarc Basins: Tectonics and Magmatism. New York: Plenum. p. 3. ISBN 978-1-4615-1843-3.
  2. Villimor, P.; Berryman, K. R.; Ellis, S. M.; Schreurs, G.; Wallace, L. M.; Leonard, G. S.; Langridge, R. M.; Ries, W. F. (2017-10-04). "Rapid Evolution of Subduction-Related Continental Intraarc Rifts: The Taupo Rift, New Zealand". Tectonics. 36 (10): 2250–2272. Bibcode:2017Tecto..36.2250V. doi:10.1002/2017TC004715. S2CID 56356050.
  3. Waight, Tod E.; Troll, Valentin R.; Gamble, John A.; Price, Richard C.; Chadwick, Jane P. (2017-07-01). "Hf isotope evidence for variable slab input and crustal addition in basalts and andesites of the Taupo Volcanic Zone, New Zealand". Lithos. 284–285: 222–236. Bibcode:2017Litho.284..222W. doi:10.1016/j.lithos.2017.04.009. ISSN 0024-4937.
  4. Bonadonna, C.; Connor, C. B.; Houghton, B. F.; Connor, L.; Byrne, M.; Laing, A.; Hincks, T.K. (2005-03-15). "Probabilistic modeling of tephra dispersal: Hazard assessment of a multiphase rhyolitic eruption at Tarawera, New Zealand". Journal of Geophysical Research: Solid Earth. 110 (B3). Bibcode:2005JGRB..110.3203B. doi:10.1029/2003JB002896.
  5. David, Lowe. "Polynesian settlement and impacts of volcanism on early Maori society" (PDF). In Lowe, D.J. (ed.). Guidebook for 'Land and Lakes' field trip, New Zealand Society of Soil Science Biennial Conference, Rotorua, held in 27–30 November 2006. Lincoln: New Zealand Society of Soil Science. pp. 50–55.
  6. Illsley-Kemp, Finnigan; Barker, Simon J.; Wilson, Colin J. N.; Chamberlain, Calum J.; Hreinsdóttir, Sigrún; Ellis, Susan; Hamling, Ian J.; Savage, Martha K.; Mestel, Eleanor R. H.; Wadsworth, Fabian B. (2021-06-01). "Volcanic Unrest at Taupō Volcano in 2019: Causes, Mechanisms and Implications". Geochemistry, Geophysics, Geosystems. 22 (6): 1–27. Bibcode:2021GGG....2209803I. doi:10.1029/2021GC009803.
  7. de Lange, Willem; Moon, Vicki (2016). Volcanic generation of tsunamis: Two New Zealand palaeo-eventsin Submarine Mass Movements and their Consequences (PDF). 56.{{cite book}}: CS1 maint: location (link)
  8. Dunbar, Nelia W.; Iverson, Nels A.; Van Eaton, Alexa R.; Sigl, Michael; Alloway, Brent V.; Kurbatov, Andrei V.; Mastin, Larry G.; McConnell, Joseph R.; Wilson, Colin J. N. (2017-09-25). "New Zealand supereruption provides time marker for the Last Glacial Maximum in Antarctica". Scientific Reports. 7 (1): 12238. Bibcode:2017NatSR...712238D. doi:10.1038/s41598-017-11758-0. PMC 5613013. PMID 28947829.
  9. "Rotorua". Global Volcanism Program. Smithsonian Institution. Retrieved 2010-08-31.
  10. Gamble, J. A.; Wright, I. C.; Baker, J. A. (1993). "Seafloor geology and petrology in the oceanic to continental transition zone of the Kermadec-Havre-Taupo Volcanic Zone arc system, New Zealand". New Zealand Journal of Geology and Geophysics. 36 (4): 417–435. doi:10.1080/00288306.1993.9514588. Archived from the original on 2008-11-22.
  11. Caratori Tontini, F.; Bassett, D.; de Ronde, C. E. J.; Timm, C.; Wysoczanski, R. (2019). "Early evolution of a young back-arc basin in the Havre Trough" (PDF). Nature Geoscience. 12 (10): 856–862. Bibcode:2019NatGe..12..856C. doi:10.1038/s41561-019-0439-y. S2CID 202580942.
  12. Parson, L. M.; Wright, I. C. (1996). "The Lau-Havre-Taupo back-arc basin: A southward-propagating, multi-stage evolution from rifting to spreading". Tectonophysics. 263 (1–4): 1–22. Bibcode:1996Tectp.263....1P. doi:10.1016/S0040-1951(96)00029-7.
  13. Villamor, P.; Berryman, K. R. (2006). "Evolution of the southern termination of the Taupo Rift, New Zealand". New Zealand Journal of Geology and Geophysics. 49: 23–37. doi:10.1080/00288306.2006.9515145.
  14. Easton, Paul (15 September 2007). "Central North Island sitting on magma film". The Dominion Post. Retrieved 16 March 2008.
  15. Heise, W.; Bibby, H.M.; Caldwell, T.G. (2007). "Imaging magmatic Processes in the Taupo Volcanic Zone (New Zealand) with Magnetotellurics" (PDF). Geophysical Research Abstracts. 9. 01311.
  16. Cole, J.W. (1990). "Structural control and origin of volcanism in the Taupo volcanic zone, New Zealand". Bulletin of Volcanology. 52 (6): 445–459. Bibcode:1990BVol...52..445C. doi:10.1007/BF00268925. S2CID 129091056.
  17. "New Zealand".
  18. http://www.volcano.si.edu/world/largeeruptions.cfm
  19. Newhall, Christopher G.; Dzurisin, Daniel (1988). "Historical unrest at large calderas of the world". USGS Bulletin. 1855: 1108. Citing Scott, B.J. (1986). Gregory, J.G.; Watters, W.A. (eds.). "Volcanic hazards assessment in New Zealand: Monitoring at Okataina Volcanic Centre". New Zealand Geol. Surv. Rec. 10: 49–54.
  20. Okataina Volcanic Center, New Zealand
  21. Nairn, I.A. (2002). Geology of the Okatania Volcanic Centre. Geological Map 25. Institute of Geological and Nuclear Sciences. p. 156.
  22. Hodgson, K. A.; Nairn, I. A. (August 2004). "The Sedimentation and Drainage History of Haroharo Caldera and The Tarawera River System, Taupo Volcanic Zone, New Zealand" (PDF). Operations Publication 2004/03. Environment Bay of Plenty: 7. ISSN 1176-5550. Archived from the original (PDF) on 2010-05-22.
  23. Krippner, Stephen J. P.; Briggs, Roger M.; Wilson, Colin J. N.; Cole, James W. (1998). "Petrography and geochemistry of lithic fragments in ignimbrites from the Mangakino Volcanic Centre: implications for the composition of the subvolcanic crust in western Taupo Volcanic Zone, New Zealand". New Zealand Journal of Geology and Geophysics. 41 (2): 187–199. doi:10.1080/00288306.1998.9514803.
  24. Cole, J. W.; Spinks, K. D. (2009). "Caldera volcanism and rift structure in the Taupo Volcanic Zone, New Zealand". Special Publications. London: Geological Society. 327 (1): 9–29. Bibcode:2009GSLSP.327....9C. doi:10.1144/SP327.2. S2CID 131562598.
  25. Hiess, J; Cole, JW; Spinks, KD (2007). High-Alumina Basalts of the Taupo Volcanic Zone, New Zealand: Influence of the Crust and Crustal Structure (PDF). p. 36. Part of a BSc Project by Hiess, J. (University of Canterbury).{{cite book}}: CS1 maint: postscript (link)
  26. Gravley, D. M.; Wilson, C. J. N.; Rosenberg, M. D.; Leonard, G. S. (2006). "The nature and age of Ohakuri Formation and Ohakuri Group rocks in surface exposures and geothermal drillhole sequences in the central Taupo Volcanic Zone, New Zealand". New Zealand Journal of Geology and Geophysics. 49 (3): 305–308. doi:10.1080/00288306.2006.9515169. S2CID 129012659.
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