A supervolcano is a large volcano that has had an eruption with a Volcanic Explosivity Index (VEI) of 8, the largest recorded value on the index. This means the volume of deposits for that eruption is greater than 1,000 cubic kilometers.
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.
A tuya is a flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are rare worldwide, being confined to regions which were covered by glaciers and had active volcanism during the same period.
The Tuya volcanic field is a volcanic field of tuyas located in far northern British Columbia, Canada, near the border with the Yukon Territory and focused on the area of the Tuya Range, a subrange of the Stikine Ranges of the Cassiar Mountains, though some vents are in the Kawdy Plateau, the northernmost part of the Stikine Plateau. Several small shield volcanoes, and postglacial lapilli cones and lava flows have been reported in this area. The only nonglacial volcanoes in the field are Gabrielse Cone and the West Tuya lava field.
Tuya Butte is a tuya in the Tuya Range of north-central British Columbia, Canada. It is a bit less isolated from other ranges than neighbouring Mount Josephine. Some of the other volcanoes in the area include South Tuya, Ash Mountain, and Mathews Tuya.
Ash Mountain is the highest summit in the Tuya Range of the Stikine Ranges in northcentral British Columbia, Canada, located immediately north of High Tuya Lake at the north end of Tuya Mountains Provincial Park. It is one of the six tuyas clustered close to Tuya Lake. The base of the volcano comprises pillow lava and hyaloclastite indicating that the volcano formed beneath ice or under a large lake. The volcano comprises loose debris as well as dikes of basaltic rock that intruded into the volcanic pile. Other tuyas in the area include Tuya Butte, South Tuya and Mathews Tuya, although most of the group of tuyas are unnamed.
Caribou Tuya is a basaltic subglacial mound in far northwestern British Columbia that began eruptive activity under glacial ice during the Fraser glaciation. Like Ash Mountain and South Tuya, sections of the subglacial mound reveal a consistent stratigraphic progression from pillow lavas to hyaloclastite deposits from the base upward. Locally the sections are capped by subaerial basaltic lava flows. Samples of the glassy pillow basalts and hyaloclastites along with crystalline basalt flows were collected at Caribou Tuya. The volcano is believed to have formed and last erupted during the Pleistocene Epoch.
South Tuya, also called Southern Tuya, is a tuya clustered around Tuya Lake in the Northern Cordilleran Volcanic Province in British Columbia, Canada. The base of South Tuya comprises hyaloclastite and pillow lava indicating that the volcano formed beneath a large lake or beneath ice.
Several types of volcanic eruptions—during which lava, tephra, and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often named after famous volcanoes where that type of behavior has been observed. Some volcanoes may exhibit only one characteristic type of eruption during a period of activity, while others may display an entire sequence of types all in one eruptive series.
Level Mountain is a large volcanic complex in the Northern Interior of British Columbia, Canada. It is located 50 km (31 mi) north–northwest of Telegraph Creek and 60 km (37 mi) west of Dease Lake on the Nahlin Plateau. With a maximum elevation of 2,164 m (7,100 ft), it is the second highest of four large complexes in an extensive north–south trending volcanic region. Much of the mountain is gently-sloping; when measured from its base, Level Mountain is about 1,100 m (3,600 ft) tall, slightly taller than its neighbour to the northwest, Heart Peaks. The lower, broader half of Level Mountain consists of a shield-like edifice while its upper half has a more steep, jagged profile. Its broad summit is dominated by the Level Mountain Range, a small mountain range with prominent peaks cut by deep valleys. These valleys serve as a radial drainage for several small streams that flow from the mountain. Meszah Peak is the only named peak in the Level Mountain Range.
Volcanism of Western Canada has produced lava flows, lava plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, greenstone belts, submarine volcanoes, calderas, diatremes and maars, along with examples of more less common volcanic forms such as tuyas and subglacial mounds.
The Mess Lake Lava Field is a volcanic field associated with the Mount Edziza volcanic complex of the Northern Cordilleran Volcanic Province in northwestern British Columbia, Canada. It lies northwest of the Spectrum Range on the Kitsu Plateau and consists of young basaltic lava flows and tephra. The source for the basaltic lava and tephra was three cinder cones, including Mess Lake Cone and The Ash Pit, which may be the youngest volcanic feature of the Mount Edziza volcanic complex.
The volcanic history of the Northern Cordilleran Volcanic Province presents a record of volcanic activity in northwestern British Columbia, central Yukon and the U.S. state of easternmost Alaska. The volcanic activity lies in the northern part of the Western Cordillera of the Pacific Northwest region of North America. Extensional cracking of the North American Plate in this part of North America has existed for millions of years. Continuation of this continental rifting has fed scores of volcanoes throughout the Northern Cordilleran Volcanic Province over at least the past 20 million years and occasionally continued into geologically recent times.
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. Other volcanic eruptions are also listed.
Jack Gordon Souther was an American-born Canadian geologist, volcanologist, professor and engineer. He contributed significantly to the early understanding of recent volcanic activity in the Canadian Cordillera. Many of his publications continue to be regarded as classics in their field, even now several decades after they were written.
The Canadian Cascade Arc, also called the Canadian Cascades, is the Canadian segment of the North American Cascade Volcanic Arc. Located entirely within the Canadian province of British Columbia, it extends from the Cascade Mountains in the south to the Coast Mountains in the north. Specifically, the southern end of the Canadian Cascades begin at the Canada–United States border. However, the specific boundaries of the northern end are not precisely known and the geology in this part of the volcanic arc is poorly understood. It is widely accepted by geologists that the Canadian Cascade Arc extends through the Pacific Ranges of the Coast Mountains. However, others have expressed concern that the volcanic arc possibly extends further north into the Kitimat Ranges, another subdivision of the Coast Mountains, and even as far north as Haida Gwaii.
An ice-marginal lava flow is a lava flow that comes into direct contact with a glacier or the margins of a large ice sheet. As the lava reaches the margins of an ice sheet, the front of the lava flow cools very quickly to form a barrier. Behind this barrier, the lava begins to pool, ceasing the contact between the hot lava and cold ice. The barrier is left behind as the ice retreats, leaving a thick lava front, which is in the form of a large, steep and unstable cliff face.
The Igwisi Hills are a volcanic field in Tanzania. Three tuff cones are found there, one of which is associated with a lava flow. They are one of the few locations of possibly kimberlitic lava flows on Earth.
Ciomadul is a volcano in Romania, and is known as Csomád in Hungarian. It is in the Carpathians, close to the towns of Băile Tușnad and Bixad. It is part of a volcanic chain known as the Călimani (Kelemen) – Gurghiu (Görgényi) – Harghita (Hargita) chain and lies at its southeastern end. Ciomadul consists of several lava domes with two embedded explosion craters known as Mohos and St. Ana, the latter of which contains a crater lake, Lake Sfânta Ana. The dominant volcanic rock at Ciomadul is potassium-rich dacite.
Edwards, B. R., Russell, J. K. and Simpson, K. 2011. Volcanology and petrology of Mathews Tuya, northern British Columbia: glaciovolcanic constraints on interpretations of the 0.730 Ma Cordilleran paleoclimate. Bulletin of Volcanology. 73:479-496. DOI 10.1007/s00445-010-0418-z
