The Rabaul caldera, or Rabaul Volcano, is a large

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 ...

on the tip of the

Gazelle Peninsula The Gazelle Peninsula is a large peninsula in northeastern East New Britain, Papua New Guinea located on the island of New Britain within the Bismarck Archipelago, situated in the southwestern Pacific Ocean. The Rabaul caldera is located on ...

East New Britain East New Britain is a province of Papua New Guinea, consisting of the north-eastern part of the island of New Britain and the Duke of York Islands. The capital of the province is Kokopo, not far from the old capital of Rabaul, which was largely des ...

Papua New Guinea Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...

, and derives its name from the town of

Rabaul Rabaul () is a township in the East New Britain province of Papua New Guinea, on the island of New Britain. It lies about 600 kilometres to the east of the island of New Guinea. Rabaul was the provincial capital and most important settlement in ...

inside 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 ...

. The caldera has many sub-vents, Tavurvur being the most well known for its devastating eruptions over

. The outer flanks of the highest peak, a 688-metre-high asymmetrical

pyroclastic shield In volcanology, a pyroclastic shield or ignimbrite shield is an uncommon type of shield volcano. Unlike most shield volcanoes, pyroclastic shields are formed mostly of pyroclastic and highly explosive eruptions rather than relatively fluid basal ...

, are formed by thick

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 ...

deposits. There is no sign of a pyroclastic shield along the rim of the caldera, making the location likely underwater, on the caldera's floor. Tavurvur, a

stratovolcano A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and peri ...

and a sub-vent of the caldera, is the most visibly active, continuously throwing ash. In 1994 it, and nearby Vulcan, erupted and devastated Rabaul; however, due to planning for such a catastrophe, the townsfolk were prepared and only five people were killed. One of the deaths was caused by lightning, a feature of volcanic ash clouds. In 1937, Vulcan and Tavurvur erupted simultaneously, killing 507 people. This event led to the founding of th
Rabaul Volcano Observatory
which watches over the many active volcanoes in Papua New Guinea. One eruption over several days in March 2008 released a plume of ash and water vapor that drifted northwest over the

Bismarck Sea The Bismarck Sea (, ) lies in the southwestern Pacific Ocean within the nation of Papua New Guinea. It is located northeast of the island of New Guinea and south of the Bismarck Archipelago. It has coastlines in districts of the Islands Regi ...

Subsidiary features

Stratovolcano A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and peri ...

es ** Tavurvur - 223 meters (732 feet) ** Rabalanakaia - 88 meters (289 feet) *

Pumice cone Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and s ...

s ** Vulcan - 243 meters (797 feet)

Eruptions

*535 AD: There is evidence of a large eruption at Rabaul, that may be the event recorded in chronicles of the reign of Byzantine Emperor

Justinian I Justinian I (; la, Iustinianus, ; grc-gre, Ἰουστινιανός ; 48214 November 565), also known as Justinian the Great, was the Byzantine emperor from 527 to 565. His reign is marked by the ambitious but only partly realized '' renov ...

as ruining the climate and helping to bring on the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire ...

. But it is not certain, as there are other possible culprits, including Ilopango in

El Salvador El Salvador (; , meaning " The Saviour"), officially the Republic of El Salvador ( es, República de El Salvador), is a country in Central America. It is bordered on the northeast by Honduras, on the northwest by Guatemala, and on the south ...

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

. *683 AD ± 2 years: There was a VEI force 6 eruption at Rabaul, proved by corrected

radiocarbon Carbon-14, C-14, or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method pioneered by Willard Libby and c ...

; there is an opinion that eruption formed the Rabaul Caldera sea-inlet. *1878: Vulcan cone nearby was formed during a large eruption in 1878. *1937: Tavurvur and Vulcan erupted, killing 508 people. For more information, see Rabaul#Rabaul (Tavurvur) volcano: 6 June 1937 eruption. *1950s: A government vulcanological observatory was established on the northern ridge of Rabaul caldera. *19 September 1994: Tavurvur and Vulcan erupted, destroying Rabaul airport and covering most of Rabaul town with heavy ashfall. Vulcan has remained quiet since. For more information see Rabaul#1994 eruption. *1994 to 1995: Last eruptions of Vulcan. *7 October 2006: Tavurvur erupted again, and an initial blast broke windows up to 12 kilometers away and sent an ash plume 18 km into the stratosphere. Winds blew most of the ash away from Rabaul. *2009: An eruption of Tavurvur was filmed by a BBC crew for the three-part nature documentary series ''

Lost Land of the Volcano ''Lost Land of the Volcano'' is a three-part nature documentary series produced by the BBC Natural History Unit which follows a scientific expedition to the island of New Guinea. The expedition team, which includes specialist zoologists, explor ...

'' produced by the

BBC Natural History Unit The BBC Studios Natural History Unit (NHU) is a department of BBC Studios that produces television, radio and online content with a natural history or wildlife theme. It is best known for its highly regarded nature documentaries, including '' ...

. The programme also looked at the wildlife living around the volcano and in its ash field, including

brahminy kite The brahminy kite (''Haliastur indus''), formerly known as the red-backed sea-eagle in Australia, is a medium-sized bird of prey in the family Accipitridae, which also includes many other diurnal raptors, such as eagles, buzzards, and harrie ...

rhinoceros beetle Dynastinae or rhinoceros beetles are a subfamily of the scarab beetle family (Scarabaeidae). Other common names – some for particular groups of rhinoceros beetles – include Hercules beetles, unicorn beetles or horn beetles. Over 1 ...

megapode The megapodes, also known as incubator birds or mound-builders, are stocky, medium-large, chicken-like birds with small heads and large feet in the family Megapodiidae. Their name literally means "large foot" and is a reference to the heavy legs ...

birds and land crabs. *1 January to 8 April 2010 (BGVN 35:02): Tavurvur was quiet.

July 2010 eruptions

*23 July 2010: Eruptions at Tavurvur volcano resumed after nearly seven months without ash emissions. *2–8 April 2010:

Seismicity Seismicity is a measure encompassing earthquake occurrences, mechanisms, and magnitude at a given geographical location. As such, it summarizes a region's seismic activity. The term was coined by Beno Gutenberg and Charles Francis Richter in ...

was low and variable amounts of white vapor rose from Tavurvur cone. *9 April 2010: The Rabaul Volcano Observatory (RVO) reported that deformation measurements at Rabaul caldera during the previous 3–4 months had shown an inflationary trend with a total of 4 cm of uplift. *22 July 2010: RVO detected increased seismicity (likely beneath Tavurvur cone), as a few small hybrid earthquakes, followed by small low-frequency earthquakes, then continuous volcanic tremor starting at time 1034. *23 July 2010: Tavurvur cone erupted, starting at time 1300. The eruption began with discharge of diffuse white plumes, followed by pink-gray fumes with low ash content. A strong odor of

hydrogen sulfide Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. The under ...

was noted, and a diffuse cloud rose 1 km and drifted NW. A few hours later, observers saw billowing gray clouds, accompanied by roaring and rumbling noises. Ashfall was reported in areas to the cone's NW and NNW. *23–26 July 2010: RVO reported that seismicity was variable. Ash emissions and ashfall continued in areas to the northwest. Visibility remained poor in Rabaul town (3–5 km NW of Tavurvur) due to ash made airborne by moving vehicles. Ash emissions ceased on 25 July. Later that day and into 26 July only diffuse brown-tinted vapor plumes were emitted and seismicity was very low. After this eruption, GPS data showed deflation of Tavurvur cone. Seismicity was very low, and diffuse white plumes were emitted during 26–30 July.

2013-14 eruptions

*January 2013: Tavurvur began to smolder. *March 2014: Tavurvur became quiet. *August 2014: Tavurvur woke and smoldered. *29 August 2014: Tavurvur started a VEI 3 eruption, around 3:30–4:00 AM local time (28 August 2014, 17:30–18:00 UTC) prompting concerns over disruption of flights in Australian airspace due to the large ash clouds (up to 50,000 feet, or 15 km). Communities near the volcano were evacuated, while residents of the town of

were advised to remain indoors to avoid falling ash, according to a statement from Australia's Department of Foreign Affairs and Trade. The VEI of this eruption was 3-4.

References

Images

File:Volcanic Ash Dunes.jpg, Dunes of

volcanic ash Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, created during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer ...

near Tavurvur File:Tavurvur.png, Tavurvur (right) and Rabalanakaia (left), as seen from space File:Vulcan-Volcano.png, Vulcan, as seen from space File:Tavurvur volcano edit.jpg, Ash cloud from Tavurvur's 2009 eruption, as seen from the

Solomon Sea The Solomon Sea is a sea located within the Pacific Ocean. It lies between Papua New Guinea and Solomon Islands. Many major battles were fought there during World War II. Extent The International Hydrographic Organization defines the limit ...

Image:Rabaul Volcano - STS064.jpg, Ash cloud from the September 1994 eruption, as viewed from the

Space Shuttle The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program n ...

Image:NASA RabaulVolcano PIA01767.jpg, A space radar image of the Rabaul Volcano {{clear, left

External links

Eruption history of Rabaul
(where, click at bottom of page) Active volcanoes Subduction volcanoes Calderas of Papua New Guinea Volcanoes of New Britain East New Britain Province VEI-6 volcanoes Pyroclastic shields Submarine calderas 20th-century volcanic events 21st-century volcanic events Shield volcanoes of Papua New Guinea