This timeline of volcanism on Earth includes a list of major volcanic eruptions of approximately at least magnitude 6 on the Volcanic explosivity index (VEI) or equivalent sulfur dioxide emission during the Quaternary period (from 2.58 Mya to the present). Other volcanic eruptions are also listed.
Some eruptions cooled the global climate—inducing a volcanic winter—depending on the amount of sulfur dioxide emitted and the magnitude of the eruption.[1][2] Before the present Holocene epoch, the criteria are less strict because of scarce data availability, partly since later eruptions have destroyed the evidence. Only some eruptions before the Neogene period (from 23 Mya to 2.58 Mya) are listed. Known large eruptions after the Paleogene period (from 66 Mya to 23 Mya) are listed, especially those relating to the Yellowstone hotspot, Santorini caldera, and the Taupō Volcanic Zone.
Active volcanoes such as Stromboli, Mount Etna and Kīlauea do not appear on this list, but some back-arc basin volcanoes that generated calderas do appear. Some dangerous volcanoes in "populated areas" appear many times: Santorini six times, and Yellowstone hotspot 21 times. The Bismarck volcanic arc, New Britain, and the Taupō Volcanic Zone, New Zealand, appear often too.
In addition to the events listed below, there are many examples of eruptions in the Holocene on the Kamchatka Peninsula,[3] which are described in a supplemental table by Peter Ward.[4]
Pinatubo, island of Luzon, Philippines; 1991, June 15; VEI 6; 6 to 16 km3 (1.4 to 3.8 cu mi) of tephra;[6] an estimated 20,000,000 tonnes (22,000,000 short tons) of SO 2 were emitted[2]
Novarupta, Alaska Peninsula; 1912, June 6; VEI 6; 13 to 15 km3 (3.1 to 3.6 cu mi) of lava[7][8][9]
Santa Maria, Guatemala; 1902, October 24; VEI 6; 20 km3 (4.8 cu mi) of tephra[10]
Krakatoa, Indonesia; 1883, August 26–27; VEI 6; 21 km3 (5.0 cu mi) of tephra[11]
Mount Tambora, Lesser Sunda Islands, Indonesia; 1815, Apr 10; VEI 7; 160–213 km3 (38–51 cu mi) of tephra;[12][6] an estimated 200,000,000 t (220,000,000 short tons) of SO 2 were emitted, produced the "Year Without a Summer"[13]
Grímsvötn, Northeastern Iceland; 1783–1785; Laki; 1783–1784; VEI 2; 14 km3 (3.4 cu mi) of lava, an estimated 120,000,000 t (130,000,000 short tons) of SO 2 were emitted, produced a Volcanic winter, 1783, on the North Hemisphere.[17][18]
Huaynaputina, Peru; 1600, February 19; VEI 6; 30 km3 (7.2 cu mi) of tephra[19]
Billy Mitchell, Bougainville Island, Papua New Guinea; 1580 ±20; VEI 6; 14 km3 (3.4 cu mi) of tephra[6]
Bárðarbunga, Northeastern Iceland; 1477; VEI 6; 10 cubic kilometres (2.4 cu mi) of tephra[6]
1465 mystery eruption "the location of this eruption is uncertain, as it has only been identified from distant ice core records and atmospheric events around the time of King Alfonso II of Naples's wedding; it is believed to have been VEI 7 and possibly even larger than Mount Tambora's in 1815.[20][21]
1452/1453 mystery eruption in the New Hebrides arc, Vanuatu; the location of this eruption in the South Pacific is uncertain, as it has been identified from distant ice core records; the only pyroclastic flows are found at Kuwae; 36 to 96 km3 (8.6 to 23.0 cu mi) of tephra; 175,000,000–700,000,000 t (193,000,000–772,000,000 short tons) of sulfuric acid[22][23][24]
1280(?) in Quilotoa, Ecuador; VEI 6; 21 km3 (5.0 cu mi) of tephra[6]
1257 Samalas eruption, Rinjani volcanic complex, Lombok Island, Indonesia; 40 km3 (dense-rock equivalent) of tephra, Arctic and Antarctic Ice cores provide compelling evidence to link the ice core sulfate spike of 1258/1259 A.D. to this volcano.[25][26]
This is a sortable summary of 27 major eruptions in the last 2000 years with VEI ≥6, implying an average of about 1.3 per century. The count does not include the notable VEI 5 eruptions of Mount St. Helens and Mount Vesuvius. Date uncertainties, tephra volumes, and references are also not included.
Note:
Caldera names tend to change over time. For example, Ōkataina Caldera, Haroharo Caldera, Haroharo volcanic complex, and Tarawera volcanic complex all had the same magma source in the Taupō Volcanic Zone. Yellowstone Caldera, Henry's Fork Caldera, Island Park Caldera, Heise Volcanic Field all had Yellowstone hotspot as magma source.
Kurile Lake, Kamchatka Peninsula, Russia; Golygin eruption; about 41.5 ka; VEI 7[6]
Maninjau Caldera (size: 20 x 8 km), West Sumatra; VEI 7; around 52 ka; 220 to 250 cubic kilometers (52.8 to 60.0 cu mi) of tephra.[36]
Lake Toba (size: 100 x 30 km), Sumatra, Indonesia; VEI 8; 73 ka ±4; 2,500 to 3,000 cubic kilometers (599.8 to 719.7 cu mi) of tephra; probably six gigatons of sulfur dioxide were emitted (Youngest Toba Tuff).[2][37][38][39][40]
Atitlán Caldera (size: 17 x 20 km), Guatemalan Highlands; Los Chocoyos eruption; formed in an eruption 84 ka; VEI 7; 300 km3 (72 cu mi) of tephra.[41]
Mount Aso (size: 24 km wide), island of Kyūshū, Japan; 90 ka; last eruption was more than 600 cubic kilometers (144 cu mi) of tephra.[4][42]
Mount Aso (size: 24 km wide), island of Kyūshū, Japan; 120 ka; 80 km3 (19 cu mi) of tephra.[4]
Mount Aso (size: 24 km wide), island of Kyūshū, Japan; 140 ka; 80 km3 (19 cu mi) of tephra.[4]
Puy de Sancy, Massif Central, central France; it is part of an ancient stratovolcano which has been inactive for about 220,000 years.
Emmons Lake Caldera (size: 11 x 18 km), Aleutian Range, 233 ka; more than 50 km3 (12 cu mi) of tephra.[4]
Mount Aso (size: 24 km wide), island of Kyūshū, Japan; caldera formed as a result of four huge caldera eruptions; 270 ka; 80 cubic kilometers (19 cu mi) of tephra.[4]
Uzon-Geyzernaya calderas (size: 9 x 18 km), Kamchatka Peninsula, Russia; 325–175 ka[44] 20 km3 (4.8 cu mi) of ignimbrite deposits.[45]
Pacana Caldera (size: 60 x 35 km), Altiplano-Puna Volcanic Complex, northern Chile; 4 Ma; VEI 8; 2,500 cubic kilometers (600 cu mi) of Atana Ignimbrite.[58]
Frailes Plateau, Bolivia; 4 Ma; 620 cubic kilometers (149 cu mi) of Frailes Ignimbrite E.[4][59]
Cerro Galán (size: 32 km wide), Catamarca Province, northwestern Argentina; 4.2 Ma; 510 cubic kilometers (122 cu mi) of Real Grande and Cueva Negra tephra.[4]
Yellowstone hotspot, Heise volcanic field, Idaho; Kilgore Caldera (size: 80 x 60 km); VEI 8; 1,800 cubic kilometers (432 cu mi) of Kilgore Tuff; 4.45 Ma ±0.05.[4][60]
The final eruptions in the creation of Banks Peninsula in New Zealand occurred about 9 million years ago.A major eruption of Gran Canaria took place around 14 million years ago.
Approximately 23.03 million years BP, the Neogene period and Miocene epoch begin.
Tejeda Caldera, Gran Canaria, Spain; 13.9 Ma; the 80 km3 eruption produced a composite ignimbrite (P1) of rhyolite, trachyte and basaltic materials, with a thickness of 30 metres at 10 km from the caldera center[71]
Gran Canaria shield basalt eruption, Spain; 14.5 to 14 Ma; 1,000 km3 of tholeiitic to alkali basalts[72]
Campi Flegrei, Naples, Italy; 14.9 Ma; 79 cubic kilometers (19 cu mi) of Neapolitan Yellow Tuff.[4]
Huaylillas Ignimbrite, Bolivia, southern Peru, northern Chile; 15 Ma ±1; 1,100 cubic kilometers (264 cu mi) of tephra.[4]
Yellowstone hotspot, McDermitt volcanic field (North), Trout Creek Mountains, Whitehorse Caldera (size: 15 km wide), Oregon; 15 Ma; 40 cubic kilometers (10 cu mi) of Whitehorse Creek Tuff.[4][73]
Yellowstone hotspot (?), Lake Owyhee volcanic field; 15.0 to 15.5 Ma.[74]
Yellowstone hotspot, McDermitt volcanic field (South), Jordan Meadow Caldera, (size: 10–15 km wide), Nevada/ Oregon; 15.6 Ma; 350 cubic kilometers (84 cu mi) Longridge Tuff member 2–3.[4][65][73][75]
Yellowstone hotspot, McDermitt volcanic field (South), Longridge Caldera, (size: 33 km wide), Nevada/ Oregon; 15.6 Ma; 400 cubic kilometers (96 cu mi) Longridge Tuff member 5.[4][65][73][75]
Yellowstone hotspot, McDermitt volcanic field (South), Calavera Caldera, (size: 17 km wide), Nevada/ Oregon; 15.7 Ma; 300 cubic kilometers (72 cu mi) of Double H Tuff.[4][65][73][75]
Yellowstone hotspot, McDermitt volcanic field (South), Hoppin Peaks Caldera, 16 Ma; Hoppin Peaks Tuff.[76]
Yellowstone hotspot, McDermitt volcanic field (North), Trout Creek Mountains, Pueblo Caldera (size: 20 x 10 km), Oregon; 15.8 Ma; 40 cubic kilometers (10 cu mi) of Trout Creek Mountains Tuff.[4][73][76]
Yellowstone hotspot, McDermitt volcanic field (South), Washburn Caldera, (size: 30 x 25 km wide), Nevada/ Oregon; 16.548 Ma; 250 cubic kilometers (60 cu mi) of Oregon Canyon Tuff.[4][73][75]
Yellowstone hotspot (?), Northwest Nevada volcanic field (NWNV), Virgin Valley, High Rock, Hog Ranch, and unnamed calderas; West of Pine Forest Range, Nevada; 15.5 to 16.5 Ma.[77]
Mount Lindesay (New South Wales), Australia; is part of the remnants of the Nandewar extinct volcano that ceased activity about 17 Ma after 4 million years of activity.
Oxaya Ignimbrites, northern Chile (around 18°S); 19 Ma; 3,000 cubic kilometers (720 cu mi) of tephra.[4]
La Garita Caldera erupts in the Wheeler Geologic Area, Central Colorado volcanic field, Colorado, USA, eruption several VEI 8 events (Possibly as high as a VEI 9), 5,000 cubic kilometers (1,200 cu mi) of Fish Canyon Tuff was blasted out in a single, major eruption about 27.8 million years ago.[52][86][87]
Unknown source in Ethiopia erupts 29 million years ago with at least 3,000 cubic kilometers (720 cu mi) of Green Tuff and SAM.[4]
Sam Ignimbrite in Yemen forms 29.5 million years ago, at least 5,550 cubic kilometers (1,332 cu mi) of distal tuffs associated with the ignimbrites.[88]
Jabal Kura’a Ignimbrite in Yemen forms 29.6million years ago, at least 3,700 cubic kilometers (888 cu mi) of distal tuffs associated with the ignimbrites.[88]
Paraná and Etendeka traps, Brazil, Namibia and Angola form 128 to 138 million years ago. 132 million years ago, a possible supervolcanic eruption occurred, ejecting 8,600 cubic kilometers (2,063 cu mi).[90]
Formation of the Karoo-Ferrar flood basalts begins 183 million years ago.
Scafells, Lake District, England; VEI 8; Ordovician (488.3–443.7 million years ago).
Flat Landing Brook; VEI 8, A Supervolcanic eruption occurred 466 million years ago, as it erupted in one of the largest explosive volcanic eruptions known in Earth's history with a volume of ejecta at around 2,000–12,000 cubic kilometers (480–2,879 cu mi).
The Bachelor (27.4 Ma), San Luis (27–26.8 Ma), and Creede (26 Ma) calderas partially overlap each other and are nested within the large La Garita (27.6 Ma) caldera, forming the central caldera cluster of the San Juan volcanic field, Wheeler Geologic Area, La Garita Wilderness. Creede, Colorado and San Luis Peak (Continental Divide of the Americas) are nearby. North Pass Caldera is northeastern the San Juan Mountains, North Pass. The Platoro volcanic complex lies southeastern of the central caldera cluster. The center of the western San Juan caldera cluster lies just west of Lake City, Colorado.
Emmons Lake stratovolcano (caldera size: 11 x 18 km), Aleutian Range, was formed through six eruptions. Mount Emmons, Mount Hague, and Double Crater are post-caldera cones.[6]
Topographically visible calderas: South part of the McDermitt volcanic field (four overlapping and nested calderas), West of McDermitt; Cochetopa Park Caldera, West of the North Pass; Henry's Fork Caldera; Banks Peninsula, New Zealand (Photo) and Valles Caldera. Newer drawings show McDermitt volcanic field (South), as five overlapping and nested calderas. Hoppin Peaks Caldera is included too.
Kiloannum (ka), is a unit of time equal to one thousand years. Megaannum (Ma), is a unit of time equal to one million years, one can assume that "ago" is implied.
The global dimming through volcanism (ash aerosol and sulfur dioxide) is quite independent of the eruption VEI.[104][105][106] When sulfur dioxide (boiling point at standard state: -10 °C) reacts with water vapor, it creates sulfate ions (the precursors to sulfuric acid), which are very reflective; ash aerosol on the other hand absorbs ultraviolet.[107] Global cooling through volcanism is the sum of the influence of the global dimming and the influence of the high albedo of the deposited ash layer.[108] The lower snow line and its higher albedo might prolong this cooling period.[109] Bipolar comparison showed six sulfate events: Tambora (1815), Cosigüina (1835), Krakatoa (1883), Agung (1963), and El Chichón (1982), and the 1808 mystery eruption.[110] And the atmospheric transmission of direct solar radiation data from the Mauna Loa Observatory (MLO), Hawaii (19°32'N) detected only five eruptions:[111]
Ring of Fire – Region around the rim of the Pacific Ocean where many volcanic eruptions and earthquakes occur
Stratospheric sulfur aerosols – Putting particles in the stratosphere to reflect sunlight to limit global heatingPages displaying short descriptions of redirect targets
Supervolcano – Volcano that has erupted 1000 cubic km of lava in a single eruption
^Miller et al.. 2012. "Abrupt onset of the Little Ice Age triggered by volcanism and sustained by sea-ice/ocean feedbacks" Geophysical Research Letters39, January 31
^De Klerk, Pim; Janke, Wolfgang; Kühn, Peter; Theuerkauf, Martin (2008). "Environmental impact of the Laacher See eruption at a large distance from the volcano: Integrated palaeoecological studies from Vorpommern (NE Germany)". Palaeogeography, Palaeoclimatology, Palaeoecology. 270 (1–2): 196–214. Bibcode:2008PPP...270..196D. doi:10.1016/j.palaeo.2008.09.013.
^Baales, Michael; Jöris, Olaf; Street, Martin; Bittmann, Felix; Weninger, Bernhard; Wiethold, Julian (November 2002). "Impact of the Late Glacial Eruption of the Laacher See Volcano, Central Rhineland, Germany". Quaternary Research. 58 (3): 273–288. Bibcode:2002QuRes..58..273B. doi:10.1006/qres.2002.2379. S2CID53973827.
^Carey, Steven N.; Sigurdsson, Haraldur (1980). "The Roseau Ash: Deep-sea Tephra Deposits from a Major Eruption on Dominica, Lesser Antilles Arc". Journal of Volcanology and Geothermal Research. 7 (1–2): 67–86. Bibcode:1980JVGR....7...67C. doi:10.1016/0377-0273(80)90020-7.
^Alloway, Brent V.; Agung Pribadi; John A. Westgate; Michael Bird; L. Keith Fifield; Alan Hogg; Ian Smith (30 October 2004). "Correspondence between glass-FT and 14C ages of silicic pyroclastic flow deposits sourced from Maninjau caldera, west-central Sumatra". Earth and Planetary Science Letters. 227 (1–2). Elsevier: 121–133. Bibcode:2004E&PSL.227..121A. doi:10.1016/j.epsl.2004.08.014.
^Jones, S.C. (2007) The Toba supervolcanic eruption: Tephra-fall deposits in India and Paleoanthropological implications; in The evolution and history of human populations in South Asia (eds.) M D Petraglia and B Allchin (New York: Springer Press) pp. 173–200
^Ninkovich, D.; N.J. Shackleton; A.A. Abdel-Monem; J.D. Obradovich; G. Izett (7 December 1978). "K−Ar age of the late Pleistocene eruption of Toba, north Sumatra". Nature. 276 (5688). Nature Publishing Group: 574–577. Bibcode:1978Natur.276..574N. doi:10.1038/276574a0. S2CID4364788.
^Uzon, Global Volcanism Program, Smithsonian Institution
^Sruoga, Patricia; Eduardo J. Llambías; Luis Fauqué; David Schonwandt; David G. Repol (September 2005). "Volcanological and geochemical evolution of the Diamante Caldera–Maipo volcano complex in the southern Andes of Argentina (34°10′S)". Journal of South American Earth Sciences. 19 (4): 399–414. Bibcode:2005JSAES..19..399S. doi:10.1016/j.jsames.2005.06.003. hdl:11336/75928.
^Karlstrom, K.; Crow, R.; Peters, L.; McIntosh, W.; Raucci, J.; Crossey, L.; Umhoefer, P. (2007). "40Ar/39Ar and field studies of Quaternary basalts in Grand Canyon and model for carving Grand Canyon: Quantifying the interaction of river incision and normal faulting across the western edge of the Colorado Plateau". GSA Bulletin. 119 (11/12): 1283–1312. Bibcode:2007GSAB..119.1283K. doi:10.1130/0016-7606(2007)119[1283:AAFSOQ]2.0.CO;2.
^Hildreth, W. (1979), Sarna-Wojcicki et al. (2000).
^Lindsay J. M.; de Silva S.; Trumbull R.; Emmermann R.; Wemmer K. (2001). "La Pacana caldera, N. Chile: a re-evaluation of the stratigraphy and volcanology of one of the world's largest resurgent calderas". Journal of Volcanology and Geothermal Research. 106 (1–2): 145–173. Bibcode:2001JVGR..106..145L. doi:10.1016/S0377-0273(00)00270-5.
^Salisbury, M. J.; Jicha, B. R.; de Silva, S. L.; Singer, B. S.; Jimenez, N. C.; Ort, M. H. (21 December 2010). "40Ar/39Ar chronostratigraphy of Altiplano-Puna volcanic complex ignimbrites reveals the development of a major magmatic province". Geological Society of America Bulletin. 123 (5–6): 821–840. Bibcode:2011GSAB..123..821S. doi:10.1130/B30280.1.
^Coombs, D. S., Dunedin Volcano, Misc. Publ. 37B, pp. 2–28, Geol. Soc. of N. Z., Dunedin, 1987.
^Coombs, D. S., R. A. Cas, Y. Kawachi, C. A. Landis, W. F. Mc-Donough, and A. Reay, Cenozoic volcanism in north, east and central Otago, Bull. R. Soc. N. Z., 23, 278–312, 1986.
^Bishop, D.G., and Turnbull, I.M. (compilers) (1996). Geology of the Dunedin Area. Lower Hutt, NZ: Institute of Geological & Nuclear Sciences. ISBN0-478-09521-X.
^Sawyer, David A.; R. J. Fleck; M. A. Lanphere; R. G. Warren; D. E. Broxton; Mark R. Hudson (October 1994). "Episodic caldera volcanism in the Miocene southwestern Nevada volcanic field: Revised stratigraphic framework, 40Ar/39Ar geochronology, and implications for magmatism and extension". Geological Society of America Bulletin. 106 (10): 1304–1318. Bibcode:1994GSAB..106.1304S. doi:10.1130/0016-7606(1994)106<1304:ECVITM>2.3.CO;2.
^ abcdefLipman, P.W. (September 30, 1984). "The Roots of Ash Flow Calderas in Western North America: Windows Into the Tops of Granitic Batholiths". Journal of Geophysical Research. 89 (B10): 8801–8841. Bibcode:1984JGR....89.8801L. doi:10.1029/JB089iB10p08801.
^ abcdSteve Ludington; Dennis P. Cox; Kenneth W. Leonard & Barry C. Moring (1996). "Chapter 5, Cenozoic Volcanic Geology in Nevada"(PDF). In Donald A. Singer (ed.). An Analysis of Nevada's Metal-Bearing Mineral Resources. Nevada Bureau of Mines and Geology, University of Nevada. Archived from the original(PDF) on 2006-02-04.
^Matthew A. Coble & Gail A. Mahood (2008). New geologic evidence for additional 16.5–15.5 Ma silicic calderas in northwest Nevada related to initial impingement of the Yellowstone hot spot. Earth and Environmental Science. Vol. 3. Collapse Calderas Workshop, IOP Conf. Series. p. 012002. Bibcode:2008E&ES....3a2002C. doi:10.1088/1755-1307/3/1/012002.
^Carson, Robert J.; Pogue, Kevin R. (1996). Flood Basalts and Glacier Floods:Roadside Geology of Parts of Walla Walla, Franklin, and Columbia Counties, Washington. Washington State Department of Natural Resources (Washington Division of Geology and Earth Resources Information Circular 90).
^ abIngrid Ukstins Peate; Joel A. Baker; Mohamed Al-Kadasi; Abdulkarim Al-Subbary; Kim B. Knight; Peter Riisager; Matthew F. Thirlwall; David W. Peate; Paul R. Renne; Martin A. Menzies (2005). "Volcanic stratigraphy of large-volume silicic pyroclastic eruptions during Oligocene Afro-Arabian flood volcanism in Yemen". Bulletin of Volcanology. 68 (2): 135–156. Bibcode:2005BVol...68..135P. doi:10.1007/s00445-005-0428-4. S2CID140160158..
^George A. Morris & Robert A. Creaser (2003). "Crustal recycling during subduction at the Eocene Cordilleran margin of North America: a petrogenetic study from the southwestern Yukon". Canadian Journal of Earth Sciences. 40 (12): 1805–1821. Bibcode:2003CaJES..40.1805M. doi:10.1139/e03-063.
^Sur l'âge des trapps basaltiques (On the ages of flood basalt events); Vincent E. Courtillot & Paul R. Renneb; Comptes Rendus Geoscience; Vol: 335 Issue: 1, January, 2003; pp: 113–140
^"Stratigraphic Chart 2022"(PDF). International Stratigraphic Commission. February 2022. Retrieved 25 April 2022.
^Fialko, Y., and M. Simons, Evidence for on-going inflation of the Socorro magma body, New Mexico, from interferometric synthetic aperture radar imaging Geop. Res. Lett., 28, 3549–3552, 2001.
^Doell, R.R., Dalrymple, G.B., Smith, R.L., and Bailey, R.A., 1986, Paleomagnetism, potassium-argon ages, and geology of rhyolite and associated rocks of the Valles Caldera, New Mexico: Geological Society of America Memoir 116, p. 211-248.
^Izett, G.A., Obradovich, J.D., Naeser, C.W., and Cebula, G.T., 1981, Potassium-argon and fission-track ages of Cerro Toledo rhyolite tephra in the Jemez Mountains, New Mexico, in Shorter contributions to isotope research in the western United States: U.S. Geological Survey Professional Paper 1199-D, p. 37-43.
^Christiansen, R.L., and Blank, H.R., 1972, Volcanic stratigraphy of the Quaternary rhyolite plateau in Yellowstone National Park: U.S. Geological Survey Professional Paper 729-B, p. 18.
^Jones, G.S., Gregory, J.M., Scott, P.A., Tett, S.F.B., Thorpe, R.B., 2005. An AOGCM model of the climate response to a volcanic super-eruption. Climate Dynamics 25, 725–738
^Jones, P.D., Wigley, T.M.I, and Kelly, P.M. (1982), Variations in surface air temperatures: Part I. Northern Hemisphere, 1881–1980: Monthly Weather Review, v.110, p. 59-70.
Newhall, Christopher G., Dzurisin, Daniel (1988); Historical unrest at large calderas of the world, USGS Bulletin 1855, p. 1108 [1]Archived 2009-05-12 at the Wayback Machine
Simkin T. & Siebert L. (1994). Volcanoes of the World. Geoscience Press, Tucson, 2nd edition. p. 349. ISBN978-0-945005-12-4.
Simkin T. & Siebert L. (2000). "Earth's volcanoes and eruptions: an overview". In Sigurdsson, H. (ed.). Encyclopedia of Volcanoes. San Diego: Academic Press. pp. 249–261.
![Harney Basin, Steens Mountain, Owyhee and Malheur River.[83]](http://en.wikipedia.org/wiki/File:Wpdms_shdrlfi020l_harney_basin.jpg)
