Example of the formation of a caldera, the pictures show Mount Mazama's eruption timeline

A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption. They are sometimes confused with volcanic craters. The word comes from Spanish caldera, and this from Latin CALDARIA, meaning "cooking pot." In some texts the English term cauldron is also used.

In 1815, the German geologist Leopold von Buch visited the Las Cañadas caldera of Teide on Tenerife, and the Caldera de Taburiente on La Palma, both in the Canary Islands. When he published his memoirs he introduced the term caldera into the geological vocabulary.

Caldera formation[link]

Animation of analogue experiment showing origin of volcanic caldera in box filled with flour

Landsat image of Lake Toba, on the island of Sumatra, Indonesia. A resurgent dome formed the island of Samosir. (100 km/62 mi long and 30 km/19 mi wide, a caldera of the world's largest class)

A collapse is triggered by the emptying of the magma chamber beneath the volcano, usually as the result of a large volcanic eruption. If enough magma is ejected, the emptied chamber is unable to support the weight of the volcanic edifice above it. A roughly circular fracture, the ring fault, develops around the edge of the chamber. Ring fractures serve as feeders for fault intrusions which are also known as ring dykes. Secondary volcanic vents may form above the ring fracture. As the magma chamber empties, the center of the volcano within the ring fracture begins to collapse. The collapse may occur as the result of a single cataclysmic eruption, or it may occur in stages as the result of a series of eruptions. The total area that collapses may be hundreds or thousands of square kilometers.

Explosive calderas[link]

If the magma is rich in silica, the caldera is often filled in with ignimbrite, tuff, rhyolite, and other igneous rocks. Silica-rich magma has a high viscosity, and therefore does not flow easily like basalt. As a result, gases tend to become trapped at high pressure within the magma. When the magma approaches the surface of the Earth, the rapid off-loading of overlying material causes the trapped gases to decompress rapidly, thus triggering explosive destruction of the magma and spreading volcanic ash over wide areas. The lava of explosive calderas is called A'a. Further lava flows may be erupted.

If volcanic activity continues, the centre of the caldera may be uplifted in the form of a resurgent dome such as is seen at Cerro Galán, Lake Toba, Yellowstone, and so on, by subsequent intrusion of magma. A silicic or rhyolitic caldera may erupt hundreds or even thousands of cubic kilometers of material in a single event. Even small caldera-forming eruptions, such as Krakatoa in 1883 or Mount Pinatubo in 1991, may result in significant local destruction and a noticeable drop in temperature around the world. Large calderas may have even greater effects.

When Yellowstone Caldera last erupted some 650,000 years ago, it released about 1,000 km³ of material (as measured in dense rock equivalent (DRE)), covering a substantial part of North America in up to two metres of debris. By comparison, when Mount St. Helens erupted in 1980, it released ~1.2 km³ (DRE) of ejecta. The ecological effects of the eruption of a large caldera can be seen in the record of the Lake Toba eruption in Indonesia.

Toba[link]

About 75,000 years ago, this Indonesian volcano released about 2,800 km³ DRE of ejecta, the largest known eruption within the Quaternary Period (last 1.8 million years) and the largest known explosive eruption within the last 25 million years. In the late 1990s, anthropologist Stanley Ambrose^[1] proposed that a volcanic winter induced by this eruption reduced the human population to about 2,000 - 20,000 individuals, resulting in a population bottleneck (see Toba catastrophe theory). More recently several geneticists, including Lynn Jorde and Henry Harpending have proposed that the human race was reduced to approximately five to ten thousand people.^[2] Whichever figure is right, the fact remains that the human race seemingly came close to extinction about 75,000 years ago.

Eruptions forming even larger calderas are known, especially La Garita Caldera in the San Juan Mountains of Colorado, where the 5,000 km³ Fish Canyon Tuff was blasted out in a single major eruption about 27.8 million years ago.

At some points in geological time, rhyolitic calderas have appeared in distinct clusters. The remnants of such clusters may be found in places such as the San Juan Mountains of Colorado (formed during the Oligocene, Miocene, and Pliocene periods) or the Saint Francois Mountain Range of Missouri (erupted during the Proterozoic).

Satellite photograph of the summit caldera on Fernandina Island in the Galapagos archipelago.

Non-explosive calderas[link]

Some volcanoes, such as shield volcanoes Kīlauea and Mauna Loa (respectively the most active and the largest on Earth, both on the island of Hawaii), form calderas in a different fashion. The magma feeding these volcanoes is basalt which is silica poor. As a result, the magma is much less viscous than the magma of a rhyolitic volcano, and the magma chamber is drained by large lava flows rather than by explosive events. The resulting calderas are also known as subsidence calderas, and can form more gradually than explosive calderas. For instance, the caldera atop Fernandina Island underwent a collapse in 1968, when parts of the caldera floor dropped 350 meters.^[3] Kilauea Caldera has an inner crater known as Halema‘uma‘u, which has often been filled by a lava lake.

It is very frequent for a caldera to become emptied by drainage of melted lava through a breach on the caldera's rim. The Caldera de Taburiente and the Caldereta, both in the island of La Palma (Canary Islands), are calderas emptied by a river of lava some 500,000 years ago.

Extraterrestrial calderas[link]

Since the early 1960s, it has been known that volcanism has occurred on other planets and moons in the Solar System. Through the use of manned and unmanned spacecraft, volcanism has been discovered on Venus, Mars, the Moon and Io, a satellite of Jupiter. None of these worlds have plate tectonics, which contributes approximately 60% of the Earth's volcanic activity (the other 40% is attributed to hot spot volcanism).^[4] Caldera structure is similar on all of these planetary bodies, though the size varies considerably. The average caldera diameter on Venus is 68 km. The average caldera diameter of Io is close to 40 km, and the mode is 6 km. Tvashtar Paterae is likely the largest caldera on Io with a diameter of 290 km. The average caldera diameter of Mars is 48 km, smaller than Venus. Calderas on Earth are the smallest of all planetary bodies and vary from 1.6 to 80 km as a maximum (Gottsmann 2008).

The Moon[link]

The Moon has an outer shell of low density crystalline rock that is a few hundred kilometers thick, which formed due to a rapid creation. The craters of the moon have been well preserved through time and were once thought to have been the result of extreme volcanic activity, but instead were formed by meteorites, nearly all of which took place in the first few hundred million years after the Moon formed. Around 500 million years afterward, the Moon's mantle was able to be extensively melted due to the decay of radioactive elements. Massive basaltic eruptions took place generally at the base of large impact craters. Also, eruptions may have taken place due to a magma reservoir at the base of the crust. This forms a dome, possibly the same morphology of a shield volcano where calderas universally are known to form.^[4]

Mars[link]

The volcanic activity of Mars is concentrated in two major provinces, Tharsis and Elysium. Each province contains a series of giant shield volcanoes that are similar to what we see on Earth and likely are the result of mantle hot spots. The surfaces are dominated by lava flows, and all have one or more collapse calderas.^[4] Mars has the largest volcano in the Solar System called Olympus Mons, which is more than three times the height of Mount Everest, with a diameter of 520 km (323 miles). The summit of the mountain has six nested calderas.^[5]

Venus[link]

Because there are no plate tectonics on Venus, heat is only lost by conduction through the lithosphere. This causes enormous lava flows, accounting for 80% of Venus' surface area. Many of the mountains are large shield volcanoes that range in size from 150–400 km in diameter and 2–4 km high. More than 80 of these large shield volcanoes have summit calderas averaging 60 km across.^[4]

Io[link]

Io, unusually, is heated by solid flexing due to the tidal influence of Jupiter and Io's orbital resonance with neighboring large moons Europa and Ganymede, which keeps its orbit slightly eccentric. Unlike any of the planets mentioned, Io is continuously volcanically active and contains many calderas with diameters tens of kilometers across. For example in 1979 The Voyager 1 and The Voyager 2 spotted 9 erupting volcanoes while passing Io.^[4]

Mineralization[link]

Some calderas are known to host rich ore deposits. One of the world's best preserved mineralized calderas is the Neoarchean Sturgeon Lake Caldera in northeastern Ontario, Canada.^[6]

This section requires expansion.

List of volcanic calderas[link]

See also Category:Volcanic calderas

• Africa
  • Ngorongoro Crater (Tanzania, Africa)
  • Menengai Crater (Kenya, Africa)
  • Mount Elgon (Uganda/Kenya)
  • Mount Fogo, Cape Verde
  • Erta Ale, Ethiopia
  • See Europe for calderas in the Canary Islands
• Asia
  

  

  Mt.Aso's caldera measures 25 km north-south and 18 km east-west
  

  

  Mt.Pinatubo, Philippines
  • East Asia
    • Dakantou Candera (大墈头), Shanhuyan Village, Taozhu Town, Linhai, Zhejiang, China
    • Ma'anshan Candera (马鞍山), Shishan Town (石山镇), Xiuying, Hainan, China
    • Yiyang Candera (宜洋), Yiyang, Pingnan County, Fujian (屏南县双溪镇宜洋村), China
    • Aira Caldera (Kagoshima Prefecture, Japan)
    • Kussharo(Hokkaido, Japan)
    • Kuttara(Hokkaido, Japan)
    • Mashū(Hokkaido, Japan)
    • Aso (Kumamoto Prefecture, Japan)
    • Kikai Caldera (Kagoshima Prefecture, Japan)
    • Towada (Aomori Prefecture, Japan)
    • Tazawa (Akita Prefecture, Japan)
    • Ashi (Kanagawa Prefecture, Japan)
    • Mount Halla (Jeju-do, South Korea)
  • Southeast Asia
    • Mount Pinatubo (Luzon, Philippines)
    • Taal Volcano (Luzon, Philippines)
    • Laguna de Bay (Luzon, Philippines)
    • Batur (Bali, Indonesia)
    • Krakatoa (Sunda Strait, Indonesia)
    • Lake Toba (Sumatra, Indonesia)
    • Mount Tambora (Sumbawa, Indonesia)
  • Russia
    • Tao-Rusyr Caldera (Onekotan, Russia)
• Americas
  • USA
    

    

    Crater Lake, Oregon, formed around 5,680 BC
    

    

    Aniakchak-caldera, Alaska
    

    

    Mount Pleasant Caldera, southwestern New Brunswick, Canada
    • Mount Aniakchak (Aniakchak National Monument and Preserve), (Alaska, US)
    • Crater Lake on Mount Mazama (Crater Lake National Park, Oregon, US)
    • Mount Katmai (Alaska, US)
    • La Garita Caldera (Colorado, US)
    • Long Valley (California, US)
    • Henry's Fork Caldera (Idaho, US)
    • Island Park Caldera (Idaho, Wyoming, US)
    • Newberry Volcano (Oregon, US)
    • Mount Okmok (Alaska, US)
    • Valles Caldera (New Mexico, US)
    • Yellowstone Caldera (Wyoming, US)
  • Canada
    • Silverthrone Caldera (British Columbia, Canada)
    • Mount Edziza (British Columbia, Canada)
    • Bennett Lake Volcanic Complex (British Columbia/Yukon, Canada)
    • Mount Pleasant Caldera (New Brunswick, Canada)
    • Sturgeon Lake Caldera (Ontario, Canada)
    • Mount Skukum Volcanic Complex (Yukon, Canada)
    • Blake River Megacaldera Complex (Quebec/Ontario, Canada)
      • New Senator Caldera (Quebec, Canada)
      • Misema Caldera (Ontario/Quebec, Canada)
      • Noranda Caldera (Quebec, Canada)
  • Chile
    • Chaitén, Chile
    • Cordillera Nevada Caldera
    • Laguna del Maule, Chile
    • Sollipulli, Chile
  • Ecuador
    • Pululahua Geobotanical Reserve
    • Cuicocha
  • El Salvador
    • Lake Ilopango
    • Lake Coatepeque
  • Other
    • Masaya, Nicaragua
    • Lake Atitlan, Guatemala
    • Fernandina Island, Galapagos Islands, Ecuador
    • Galán, Argentina
• Europe
  

  

  Santorini, Greece
  • Banská Štiavnica (Slovakia)
  • Bakuriani/Didveli Caldera (Georgia)
  • Samsari (Georgia)
  • Santorini (Greece)
  • Nisyros (Greece)
  • Askja (Iceland)
  • Grímsvötn (Iceland)
  • Katla (Iceland)
  • Krafla (Iceland)
  • Campi Flegrei (Italy)
  • Lake Bracciano (Italy)
  • Lake Bolsena (Italy)
  • Las Cañadas on Teide (Spain)
  • Ardnamurchan (Scotland)
  • Laacher see (Germany)
  • Lagoa das sete cidades on Azores islands (Portugal)
• Oceania
  

  

  Satellite photo of Lake Taupo
  • Lake Rotorua (New Zealand)
  • Lake Taupo (New Zealand)
  • Maroa (New Zealand)
  • Okataina (New Zealand)
  • Reparoa (New Zealand)
  • Kilauea (Hawaii, US)
  • Moku‘āweoweo Caldera on Mauna Loa (Hawaii, US)
  • Rano Kau (Easter Island, Chile)
  • Tweed Volcano (New South Wales, Queensland), (Australia)
• Antarctica
  • Deception Island
• Indian Ocean
  • Cirque de Mafate, Cirque de Salazie, Enclos Fouqué, and Cirque de Cilaos on Réunion
• Mars
  • Olympus Mons Caldera
• Venus
  • Maat Mons Caldera

Eroded calderas[link]

• Americas
  • Mount Tehama (California, US)
• Europe
  • Caldera de Taburiente (Spain)
• Oceania
  • Mount Warning (Australia)

See also[link]

• Complex volcano
• Somma volcano
• Supervolcano
• Volcanic Explosivity Index

References[link]

• Clough, C. T; Maufe, H. B. & Bailey, E. B; 1909. "The cauldron subsidence of Glen Coe, and the Associated Igneous Phenomena". Quarterly Journal of the Geological. Society. 65, 611-678.
• Gudmundsson, A (2008). Magma-Chamber Geometry, Fluid Transport, Local Stresses, and Rock Behavior During Collapse Caldera Formation. In Gottsmann J. & Marti, J (Ed. 10) Caldera Volcanism: Analysis, Modeling, and Response (314-346) Elsener, Amsterdam, The Netherlands
• Kokelaar, B. P; and Moore, I. D; 2006. Glencoe caldera volcano, Scotland. ISBN. 0852725252. Pub. British Geological Survey, Keyworth, Nottinghamshire. There is an associated 1:25000 solid geology map.
• Lipman, P; 1999. "Caldera". In Haraldur Sigurdsson, ed. Encyclopedia of Volcanoes. Academic Press. ISBN 0-12-643140-X
• Williams, H; 1941. Calderas and their origin. California University Publ. Geol. Sci. 25, 239-346.

External links[link]

Wikimedia Commons has media related to: Caldera

• USGS page on calderas
• List of Caldera Volcanoes
• Collection of references on collapse calderas (43 pages)
• The Caldera of the Tweed Volcano - Australia
• Largest Explosive Eruptions: New results for the 27.8 Ma Fish Canyon Tuff and the La Garita caldera, San Juan volcanic field, Colorado
• Supervolcanoes

Junior Caldera is a French disc jockey from Paris. A multi-instrumentalist, Caldera was influenced by many musical styles and made rock music before becoming involved in house music in 2002 whilst working as a stage designer in a number of Parisian nightclubs.^[1] To date, he has released one studio album and three official singles, two of which have reached the top 40 of the French singles chart. Aside from his solo career, Caldera has produced remixes for a number of musicians, such as Paulina Rubio and Enrique Iglesias.^[2]

History[link]

Following his move into electronic music in 2002, Caldera was given a residency at D! Club in Lausanne and in 2003 he won a mixing contest and was awarded to opportunity to warm up for David Guetta.^[1] He later moved on to electronic dance music and in 2007, his track "Sexy" became popular in many French clubs, reaching the top 5 of the French Club Charts. Following this success, Caldera was invited to remix tracks by various notable artists, including the Pussycat Dolls, Enrique Iglesias and Paul Van Dyk.^[2]

Caldera continued to work on his solo career, and on 18 May 2009 he released his first studio album, Debut, which reached a peak position of #193 in the French albums chart.^[3] The album featured guest a performance from Sophie Ellis-Bextor.^[4] To date, Caldera has released three official singles; "Feel It" was released in February 2008 but failed to chart, and "Sleeping Satellite" (a house remix of the Tasmin Archer track) was brought out on 15 September 2008 and reached a respectable #37 in the French singles chart, staying in the chart for 12 weeks.^[5]

His highest charting single so far is "Can't Fight this Feeling", with Sophie Ellis-Bextor, which managed a peak position of #13 in France and has been in the chart for 17 consecutive weeks. It was also a smash hit in Russia, where it topped the charts, and was a worldwide hit on the club scene. This year, he made a remix of the song "Live Your Dreams". This song is a Soraya's (a popular spanish singer) collaboration with the very famous french DJ Antoine Clamaran. The song has been very successful and has been on the list of more than 14 countries, too. The original track (called 'Radio Edit') will be included in the new Soraya's album, 'Dreamer', on sale September 28.^[6]

Discography[link]

Albums[link]

• Debut (2009) - FRA #193^[3]

Singles[link]

• "Feel It" (2008)
• "Sleeping Satellite" (2008) - FRA #37^[5]
• "The Way" (2009) - FRA #22^[6]
• "What You Get" (2009) - FRA #14 ^[7]
• "Algo De Ti" feat. Paulina Rubio (2010) - SP #48 ^[8]
• "Can't Fight This Feeling" feat. Sophie Ellis-Bextor (2010) - FRA #13, RUS #1
• "A Little Bit More" feat. Keely Pressly (2010)
• "(It is) Blasphemy" feat. Jack Strify (2011)
• "Lights Out (Go Crazy)" feat. Natalia Kills & Far East Movement - (2012) RUS #9, CAN #85

References[link]

Natalia Kills
Natalia Kills in 2011.
Background information
Birth name	Natalia Keery-Fisher
Also known as	Verbz, Verbalicious,[1] Natalia Noemi Cappuccini,[2] Verse, Candy Rapper, Verbal
Born	(1986-08-15) 15 August 1986 (age 25) Bradford, West Yorkshire, England
Genres	Pop, electropop
Occupations	Singer-songwriter, actress, film director
Instruments	Vocals, drums, guitar
Years active	1995–present
Labels	Adventures in Music, will.i.am, Cherrytree, Interscope
Website	www.nataliakills.com

Natalia Keery-Fisher^[3][4] (born 15 August 1986) is an English singer-songwriter, actress, and director who performs under the stage name Natalia Kills. She released her debut album, Perfectionist, in 2011.

Biography[link]

1986–94: Early life[link]

Kills was born in Bradford, West Yorkshire, to an Afro-Jamaican father and Uruguayan mother,^[5] where she attended Bradford Girls' Grammar School. In addition, she studied classical drama at the London Academy of Music and Dramatic Art.^[3] She stated in a post on her blog on social website, MySpace that she grew up flying between London and Florida, where she had relatives, resulting in a mixed American and English accent.^[6]

1995–2010: Career beginnings[link]

Kills made her acting debut at age 9 in 1995 in New Voices. She had a regular role as Sima on the TV sitcom All About Me and also played Amy Franks in the BBC's long-running radio drama The Archers. She began writing songs at 14,^[7] some of which were featured in films and television shows, including Bring It On 4, Sleepover, Just My Luck, and Entourage.^[4] After finishing with The Archers in 2003, Kills began pursuing a music career and attributes her musical breakthrough to winning a Radio 1 MC Battle in Leeds under the name "Candy Rapper" in 2003.^[3] She signed to the UK record company Adventures in Music and released her first single "Don't Play Nice" under the name Verbalicious in February 2005. Kills' told W that her childhood nickname from her mother was "Verbal" because she talked and sang a lot. She adopted the name and variations of it as her stage name at some points during her career.^[8]

While writing music for films,^[9] Kills posted her self-produced and written demo extended play, Wommanequin on music social website MySpace in 2007 that attracted the attention of blogger Perez Hilton in 2008, her song received 2 million plays on the website and Kills reached the top of the unsigned artists chart.^[8] With offers coming in for concerts and festivals, Kills moved to Los Angeles.^[9] In LA, Kills was approached by producers, A&R and labels with contracts.^[9][10] A DJ introduced her to will.i.am after hearing her demo and learning that she did not have a record deal. In January 2008, will.i.am signed her to his record label, will.i.am Music Group. She did not sign right away as she had reservations about the music industry and will.i.am had to go to London a month later to convince her to record with him.^[9] During this time she also co-wrote and appeared on "They Talk Shit About Me" by French recording artist M. Pokora and met underground director Guillaume Doubet, who would go on to direct many of her videos, in Paris.

[edit] 2011—: Perfectionist

Kills explained in an interview that she adopted the stage name Natalia Kills at the behest of her record company, which found "Natalia Cappuccinni" hard to pronounce.^[9] She had taken on her grandmother's family name a few years prior.^[6] She explained in an interview that her stage name is based on the phrase "you killed it," and represents her tendecy to be a perfectionist.^[11] Kills released her debut album Perfectionist in April 2011 in Germany following a top ten placing by the first single, "Mirrors". The album was described as a concept album by Kills, chronicling the fact that perfection is attainable.^[7] It features production by Jeff Bhasker and Fernando Garibay,^[7] who had worked with Lady Gaga.^[12] The album was accompanied by four singles, "Mirrors", "Wonderland", "Free" and "Kill My Boyfriend". The first three singles were minor hits in some European countries but failed to chart in the US or UK. Kills opened for Kelis' European All Hearts Tour, as well as supported Robyn on her Body Talk Tour in November 2010 and early 2011. She also supported Ke$ha on the UK leg of her Get Sleazy Tour. Throughout August and September 2011, Kills supported Katy Perry on her California Dreams Tour for eight dates in Europe^[13] and São Paulo, Brazil. She also opened for the Black Eyed Peas over the summer of 2011 in Europe.^[8][11]

Kills is featured on a Junior Caldera's single, "Lights Out (Go Crazy)", along with Far East Movement. It was released on March 13, 2012.^[14] Kills also features in Tatana's single, "You Can't Get In My Head (If You Can't Get In My Bed)".

On April 4, 2012, the singer took to Twitter to announce she was back in the studio, potentially beginning work on her second studio album.

Influences[link]

Kills called Kate Bush and Alanis Morissette her most important musical influences, highlighting them as emotional artists who wrote honestly about their own experiences.^[15] She has also gone on to cite Gwen Stefani as her hero. She also claims that Depeche Mode, Prince, Vanity 6 and Freddie Mercury inspire her live performances.^[11]

Discography[link]

• Perfectionist (2011)

Filmography[link]

References[link]

External links[link]

• Official website
• Natalia Kills at Allmusic
• Natalia Kills at the Internet Movie Database