Full glossary

Babuyan Claro (Mt. Pangasun) is the largest and second youngest of 5 volcanoes that built up Babuyan Island, 100 km off the north coast of Luzon, Philippines. Babuyan Claro is an active stratovolcano of ca. 7 cubic km volume and has 2 summit craters of 300 and 400 m in diameter.
Smith volcano (Mt. Babuyan) 4 km to the NW of Babuyan Claro is the youngest volcano on the island and forms a beautiful 668 m high symmetrical basaltic-andesite cinder cone with ca. 3 cubic km volume.
Both Babuyan Claro and Smith volcanoes have apparently been active in historical time, although it is not always certain which volcano erupted. Eruptions at Babuyan Claro are typically strombolian and/or phreatomagmatic.
The Askedna Hot Spring is located at the southern base of Babuyan Claro.

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Mount Bachelor (formerly known as Bachelor Butte) in central Oregaon is a symmetrical stratovolcano, which is part of a 25 km long volcanic chain SE of South Sister.
The chain is aligned N-S and consists of the main volcano of Mt Bachelor itself, cinder cones, small shield volcanoes, and lava flows. The youngest eruption (dated by comparison with known dates of overlying and underlying layers) occurred about 6000 years ago at the Egan scoria cone on the north flank. It produced a lava flow that overlies (=is younger than) ash from the 6850 year BP eruption of Crater Lake.

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Bagana volcano on Bougainville Island is one of the world's most active volcanoes. It has erupted frequently since its discovery in 1842. It is located on a remote part of central Bougainville Island in the Northern Solomon Province of Papua New Guinea.
Bagana volcano is a massive, symmetrical, roughly 1750-m-high cone built largely by rapid accumulation of viscous andesitic lava flows. The present-day cone might only be 300 years old.
Major eruptions occurred in 1950, 1952, and 1966. Bagana has been in near- continuous activity since 1972, creating slow-moving lava flows, and occasionally ash explosions that sometimes produce pyroclastic flows.
The volcano has been in near-continuous activity since the earliest records from the 18th century.

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Changbaishan (or Baitoushan) volcano is a large stratovolcano at the NE China - N Korean border and is and the most active in China.
It is also known as Tianchi, or in Korean as Baegdu or P'aektu-san (Paektusan) volcano.
One of the largest explosive eruptions in the world during the past 10,000 years occurred around 969 ±20 AD and is known as the Baitoushan eruption. It erupted about 30 cubic km of magma, about half as much as Tambora in 1815 AD or 3 times as much as Krakatau in 1883. The eruption produced rhyolitic and trachytic pumice and ash fall as far as northern Japan, and formed part of the present-day caldera.
Small eruptions have been recorded in historic times since the 15th century, the last being a small explosion in April 1903.
Out of China's 14 active volcanoes, Baitoushan is considered the most dangerous volcano. The major hazard are lahars from the huge lake in the 5-km-wide caldera that could threaten the mostly Korean population of about 100,000 living near or on the slopes of the volcano, as well as the many tourists visiting the volcano in summer.

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Bakanovi volcano is an extinct volcano 16 km east of Bagana volcano on Bougainville Island, Papua New Guinea. The small volcano is deeply eroded and was built above an eroded 4 km diameter caldera.

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Balagan-Tas volcano (also known as Indigirsky) is a cinder cone west of the town Zashiversk, about 1300 km SSW of Bennet Island in Siberia. It is located at the Indikirika River near the northwest boundary of Momo-Selenniak depression.
The volcano erupted basaltic lava flows. A historic eruption is reported to have taken place in 1775, but not included in the Smithsonian's Global Volcanism Database.

Balatukan (also known as Balingoan or Balatocan) is a massive compound stratovolcano on the SW shore of Gingoog Bay, 15 km SW of Gingoog city in north-central Mindanao, opposite Camiguin Island, Philippines.
Lava flows on its flanks are 140,000 years old and it is not known whether there are younger volcanic products. Although the volcano still has fumarolic activity, it might be extinct, as the strong degree of erosion of its flanks suggests.

Balbi is a large stratovolcano and the highest point on Bougainville Island, Northern Solomon Islands, Papua New Guinea.
It is not certain whether the volcano has erupted in historic times, as some local traditions suggest. An active fumarole field is located at Balbi's 600 m wide summit crater and on its western flank.

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Bald Knoll is the youngest of a group of basaltic cinder cones on the SW part of the Paunsaugunt Plateau in southern Utah, between the southern end of Bryce Canyon National Park and the western margin of Grand Staircase-Escalante National Monument.
The Bald Knoll cinder cone probably erupted only a few thousands years ago. It has an intact crater, which has produced a massive youthful-looking lava flow that traveled about 12 km to the SSE.
Buck Knoll and Black Knoll are 2 other cinder cones to the west, located on the western side of Kanab Creek.

Baluan volcano forms the a small 5.5 km wide circular Baluan Island located south of Manus Island.
It is the subarial part of the southernmost and largest single volcano in the St Andrew Strait in the Bismarck Sea northwest of New Britain.
Baluan is mainly basaltic in composition. The island is densely forested and the volcano contains a large 1 x 0.5 km elliptic vegetated summit crater (Sabroma) and several flank vents. Some of these might be less than 10,000 years old.
There are warm springs along the coast which is surrounded by reefs.
The only historical activity is an uncertain report of a submarine eruption near the island in 1931.

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Baluran is the easternmost volcano in Java and occupied the NE tip of the island. Gunung Baluran is a small andestic volcano with a broad U-shaped crater breached to the NE.
Baluran is located in the Baluran National Park which covers 25,000 hectares and is famous for its abundant wildlife including buffalo, deer, banteng, leaf monkeys, monitor lizards, squirrels, fruit bats, civet cats, and leopards.

Balut volcano (also known as Sanguil) is a small island of the Sarangani group south of the Batulaki Peninsula at the south end of Mindanao Island in the Philippines.
The age of the last activity on Balut volcano is unknown, but hot springs and thermal areas are active on the W and SW flanks of the volcano.

Bam volcano is one of the most active volcanoes in Papua New Guinea. A mostly submerged stratovolcano forms the small 2.4 km x 1.6 km oval shaped Bam Island. Bam volcano belongs to the Bismarck volcanic arc north of New Guinea. Bam is the SE-most of the Schouten Islands and ocated 40 km NNE of the mouth of the Sepik River.
Bam volcano contains 2 peaks, the NW peak being the active summit, and the SE peak an older cone and slightly lower.
The oval 300 m diameter and 180 m deep summit crater of Bam is free of vegetation due to frequent and recent volcanic activity. The crater has steep walls with exposed lava flows dipping inwards.
The historic eruptions, recorded since 1872, were small to moderate vulcanian eruptions from the summit crater. Hot springs are found on the island.

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Bamaoqiongzong volcano is a large shield volcano of unknown, but Quarternary age in NE Tibet. It covers an area of 300 sq km and contains a perfectly preserved edifice NE of the summit and a lava flow that overlies Quaternary lake deposits.

Bamus volcano (also known as South Son, Ulawun being the father) is a symmetrical stratovolcano SW of Ulawun volcano, 16 km inland from Stettin Bay.
The volcano is thickly covered by rainforest and fern thickets. The last confirmed activity of Bamus was around 1888, as villagers describe in local accounts.

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Banahaw volcano is a complex of 3 volcanoes 80 km SE of Manila, Philippines. The Banahaw volcanic complex includes Mt Banahaw (2158 m), San Cristobal (1470 m), and Banhao de Lucban (1870 m) volcanoes.
Mild explosive eruptions might still occur at the Banahaw volcano complex, although none of the reports of historic activity can be verified by deposits or credited sources.

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Banda Api volcano forms a small isolated 3-km-wide island in the Banda Sea, Indonesia, 130 km south of Makulu Island. The volcano rises 4000 m from the sea floor and is the most recent and very active cone of a 7 km wide volcanic caldera mostly under water.
It is one of the most active volcanoes in the region and is known for violent activity including tall ash emissions, lava fountaining, strombolian explosions and occasional lava flows, some of which which have reached the sea. Because of its (for Indonesia) unusually effusive behavior and frequent activity, Banda Api has also been given the nickname "Etna of the Banda Sea".

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Bandai volcano (or Bandaisan volcano), one of Japan's most known active volcanoes, is an complex andesitic stratovolcano rising above the north shore of Lake Inawashiro.
The volcano is located in the southern part of the NE Honshu volcanic arc.
The last magma was erupted at Bandai about 25,000 years ago, but during the past 5000 years, 4 major phreatic explosions have occurred at the volcano. 2 of them occurred in historical time, in 806 and 1888.
In 1888, the youngest edifice of Bandai, Ko-Bandai, collapsed in a catastrophic way after a large phreatic eruption, producing a debris avalanche that buried several villages and formed several large lakes. Seen from the south, Bandai presents a conical profile, but much of the north side of the volcano is missing as a result of the collapse of Ko-Bandai volcano during the 1888 eruption.

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Banua Wuhu is a submarine volcano in the Sangihe Islands, Indonesia, 45 km south of Awu. The volcano rises more than 400 m from the sea floor and almost reaches the surface, forming a shallow shoal at 5 m depth. Banua Wuhu, during some of its eruptions, has created temporary islands, which were eroded subsequently by wave action. Adjacent Mahengetang island belongs to the same volcanic edifice. Separate vents are found to the northeast (Kahakitang) and north (Kalama) of Banua Wuhu.

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Baransky volcano (Sashiusu-dake or Sashiusudake in Japanese) is a stratovolcano in the center of Iturup Island, southern Kuriles. Only one historical eruption occurred in 1951 and consisted of weak explosions in the summit crater.
Strong fumarolic activity is in the summit and several flank craters. A geothermal field is found on the SW flank and contains hot springs and geysers. During a geothermal exploration in 1992 in this field, a small hydrothermal explosion took place inside an exploratory well and the exploration was abandoned.

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Barcena volcano forms the southern part and most significant feature of Isla San Benedicto, the 3rd largest and north-easternmost of the 4 Islas Revillagigedo islands about 350 km south of Cabo San Lucas, Baja California.
The volcano formed by eruptions during 1952-53 and consists in a 700 m wide and 330 m high tuff cone with a circular crater and a spectacular lava delta on the east side formed by a trachytic lava flow that breached the crater and entered the sea. The eruption was the first historic eruption witnessed in the eastern Pacific Ocean.

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Bardarbunga (Bárðarbunga) is a large central volcano lying underneath Iceland's 500-m thick Vatnajokull glacier in the center of the country. It is located at the junction between the eastern and northern volcanic rift zones in the area where the present-day center of the mantle hot spot beneath Iceland is thought to be.
Bardarbunga has had about 300-400 eruptions during the past 10,000 years which includes only 23 eruptions historic times (approx the past 1000 years), i.e. it seems to erupt currently at rates of approx. twice per century, the last one having occurred in 1910. A massive explosive-effusive eruption (VEI 6) in 1477 resulted in a large ash and pumice fall-out deposit.
Approx 8600 years ago, Bardarbunga produced the largest known lava flow during the past 10,000 years on earth (more than 21 cubic kilometers of volume). The lava was erupted from the Veidivötn fissure system and traveled more than 100 km to the south coast.

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Barú volcano (also called Volcán de Chiriqui) is an active volcano 35 km east of the border to Costa Rica in the Talamanca Range of western in Panama. The complex, mainly andesitic stratovolcano is Panama´s highest peak.
A large explosive eruption occurred at about 700 AD destroyed settlements around the volcano. Excavations at the Cerro Punta archaeological site NW of the volcano have brought back to life their ruins.
The only historical eruption of Barú was an explosive eruption reported from the mid 16th century, but radiocarbon-dated tephra samples suggest that there was some activity less than 500 years ago.
Volcán Barú is the youngest major volcano in Panamá and there are geothermal exploration projects under way.

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Bas Dong Nai volcano (also known as the Xuan Loc Plateau) is a volcanic field in SE Vietnam, east of Ho Chi Minh city (Saigon). It could be less than 10,000 years old and is the southernmost volcanic area in mainland Vietnam. Suzanna Mount is a well-preserved 180 m high basaltic cone of prehistoric age.

The most common type of volcanic rock, with a relatively low silica content and typically erupted at shield volcanoes.

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An adjective describing the chemical composition of magmas (or lavas) having relatively low content of silica (SiO2), as opposed to "acidic", and a comparably high content of iron and magnesium.

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Batur is the most active volcano on the popular tourist island of Bali and one of Inondesia's more active ones. During the past centuries, Batur has had a number of small eruptions every few years. Thanks to the scenic beauty of the caldera with its lake and the cone of Batur, it is one of Bali's most popular destinations.

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Myojinsho is a large submarine caldera volcano in the Izu Islands arc, ca. 400 km south of Tokyo. Its most well-known feature are the Bayonnaise Rocks (ベヨネース列岩 Beyonēsu-retsugan), which represent a small exposed rim of the caldera composed of a few rocks rising just above sea level.
Myojinsho caldera is 8-9 km wide and has been known for its submarine eruptions which sometimes produce temporary islands. Most of its frequent eruptions have occurred at Myojin-sho, a large young lava dome on the NE rim of the caldera. In 1952, an explosive eruption at Myojin-sho destroyed a Japanese research vessel, killing all 31 people on board.
There is only sparse vegetation on the Bayonnaise Rocks, but the islands are an important resting place for migratory birds. Located in the Kuroshio Current, the waters around have abundant sea life and are popular with sports fishermen.

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Bazman volcano is a stratovolcano in SE Iran, 180 km SSW of the city of Zahedan. The volcano has a well-preserved 500 m wide summit crater with minor fumaroles, which suggest it could be still active.

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The compound Belerang-Beriti volcano rises above the Semalako Plain in SW Sumatra, forming a NW-SE-trending massif that contains a 1.2-km-wide crater breached to the NE.

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Belknap Crater volcano is located near McKenzie Pass, north of the Three Sisters volcanoes in Central Oregon. It is the center and source of one of the largest number of geologically recent eruptions in the Cascade Range. It was very active between about 3000 and 1500 years ago.
The McKenzie highway 242 crosses the barren lava fields on the SE flank and offers with spectacular views toward Mt. Jefferson and the Three Sisters volcanoes.

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Bentonite is an absorbent aluminium phyllosilicate generally impure clay consisting mostly of montmorillonite.

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Berutarube volcano (also written as Berutarubesan volcano) is an andesitic-to-dacitic stratovolcano on the SW tip of Iturup Island in the southern Kuriles. It has gentle slopes which are deeply eroded by glacial valleys. Funaroles and sufur deposits occur in the inner walls of the central crater.

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Gunung Besar is a 1899-m-high volcano in SE Sumatra with a minor sulfur deposit in its crater.

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Bezymianny ("unnamed") was considered extinct until it erupted violently in 1955-56, after a slumber of probably 1000 years. It is one of the most active volcanoes in Kamchatka. The eruption followed a massive flank failure (similar to Mt. St. Helens eruption in 1980) which removed a 0.5 sq km sector of the volcano.

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Bibinoi volcano (Bukit Bibinoi, Bibinoi Hill) on the SE tip of Bacan Island is the largest and SE most of 3 volcanoes on the island, located off the south coast of Halmahera Island, Indonesia. Two other, smaller volcanic centres are Songsu and Lansa.
Binibnoi is separated from the Amasing volcanic complex to the NW by the metamorphic (i.e. non volcanic) Sibela Mountain range.

Biliran volcano comprises the whole 20x35 km Island of Biliran which is formed by a group of lava domes. It is located across the narrow Biliran Strait from the northern tip of Leyte Island.
Biliran volcano is at the northern end of a 170 km long volcanic chain extending SSE to Panaon Island.
The only known historic activity took place on 26 September 1939 and consisted of a phreatic explosion accompanied possibly by a debris avalanche. Ash fell in Caibiran town 12 km to the E.
There are many fumarole fields, hot springs, mud pools and thermal areas on Biliran.

Billy Mitchell volcano is a small shield volcano, which is composed mainly of loose deposits from explosive eruptions (pyroclastic shield). The volcano is located immediately NE of Bagana volcano in central Bougainville Island.
Billy Mitchell's typical eruption style are explosive eruptions from the central vent, and the volcano is remarkable for having produced some of the largest explosive eruptions in Papua New Guinea in the past 10,000 years.

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Binuluan volcano belongs to the Ambalatungan volcanic group and is located in the Kalinga Province, Luzon Island, Philippines.
A possible steam eruption of Binuluan volcano in 1952 killed 12 people by a sulphur rich debris flow.

Bir Borhut volcano is an active, but almost unknown volcano in eastern Yemen near the Gulf of Aden. Old documents tell of volcanic activity in the 10th century, and it was reported to have still been "smoking" in 1813.

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The Black Rock Desert volcanic field of a group of small volcanic fields in south central Utah, at the eastern margin of the Great Basin. It is the youngest volcanic area in Utah and contains both Utah's youngest known rhyolite dome (0.4 million years old) and its youngest lava flows, the roughly 660-year-old Ice Springs lava flows, located at Ice Springs, 15 km west of Meadow. These lava flows extend 4 km north and west from Black Rock Station.

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Volcanic blocks are solidified rock fragments greater than 64 mm in diameter. Blocks commonly are ejected during explosive eruptions and consist of older pieces of the volcano's edifice, e.g. parts of the conduit, lava domes or older lava flows.

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Blue Lake is a series of at least 3 overlapping explosion craters (maars), located along a NE trend slightly east of the crest of the Cascade Range. The best-known crater, Blue Lake Crater contains a blue lake (800m x 300m) and is probably the youngest. It formed by an eruption about 1300 years ago. It lies immediately west of the popular recreation area of Suttle Lake.

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Blup Blup volcano forms the small, forested 3.5 km wide Blup Blup Island ca. 30 km offshore from Cape Girgir on the East Sepik coastline of New Guinea. The closest town is Karau.
The andesitic-dacitic volcano contains a 800 m diameter summit crater filled by thick rainforest, and possibly a lava dome on a ridge extending to the west. Lava flows with well-developed flow fronts are visible on its flanks. A small flank cone is located on the SW coast.
Most activity took place from the summit crater, but the age of the last eruption is unknown, but probably less than 10,000 years ago.