Anahim Volcanic Belt

The Anahim Volcanic Belt is a 600 km (373 mi) long volcanic belt, stretching from just north of Vancouver Island to near Quesnel, British Columbia, Canada. The Anahim Volcanic Belt has had three main magmatic episodes: 15–13 Ma, 9–6 Ma, and 3–1 Ma. The volcanoes generally become younger eastward at a rate of 2 cm (0.8 in) to 3.3 cm (1.3 in) a year. The Nazko Cone, which last erupted only 7,200 years ago, is the youngest Anahim volcano. These volcanoes are thought to have formed as a result of the North American Plate sliding westward over a long-lived center of upwelling magma called the Anahim hotspot. The hotspot is thought to be similar to the one feeding the Hawaiian Islands.

Future volcanism is most likely in the form of basaltic cinder cones, but eruptions of less mafic magma, typical of the eastern portions of the belt, cannot be ruled out. A series of earthquakes began October 9, 2007 in the vicinity of Nazko Cone which was related to intense subterranean volcanic activity in the area.

The volcanic belt is defined by 37 Quaternary basalt centers and three large shield volcanoes called the Rainbow Range, Ilgachuz Range and the Itcha Range. These three large volcanoes have built up dome-like piles of lava and fragmental rocks to a height of 8,130 feet (2,478 m) at Tsitsutl Peak in the Rainbow Range, 7,873 feet (2,400 m) at Far Mountain in the Ilgachuz Range, and 7,760 feet (2,365 m) at Mount Downton in the Itcha Range. The Rainbow Range is a low dome-like cone about 20 miles (32 km) diameter, with Anahim Peak an obsidian plug on its north-east flank. The Ilgachuz Range is 15 miles (24 km) or more in diameter, and the Itcha Range is 10 miles (16 km) wide and about 40 miles (64 km) long. All have been dissected by late Tertiary, pre-Pleistocene stream erosion.

Major volcanoes of the Anahim Volcanic Belt include:

Anahim Volcanic Belt-en
The Anahim Volcanic Belt

See also

External links

2007–2008 Nazko earthquakes

The 2007–2008 Nazko earthquakes were a series of small volcanic earthquakes measuring less than 4.0 on the Richter magnitude scale. They took place in the sparsely populated Nazko area of the Central Interior of British Columbia, Canada starting on October 9, 2007 and ending on June 12, 2008. They occurred just west of Nazko Cone, a small tree-covered cinder cone that last erupted about 7,200 years ago.

No damage or casualties resulted from the Nazko earthquakes, which were too small to be felt by people, but local seismographs recorded them. The earthquake swarm occurred at the eastern end of a known volcanic zone called the Anahim Volcanic Belt. This is an east-west trending line of volcanic formations extending from the Central Coast to the Central Interior of British Columbia.

Anahim Lake

The subject of this article should not be confused with Anaham, which is a different community located nine kilometres east of Alexis Creek, British Columbia, which is in the same area.Anahim Lake is a small community in British Columbia. The village and surrounding areas (including nearby Nimpo Lake) have a population of approximately 1500. The Ulkatcho First Nation has 729 people living on nearby reserves. Every July, the Anahim Lake Stampede showcases local talent and is the area's major social event. Anahim Lake supports three general stores, one motel, a restaurant, and an RCMP detachment. It is situated on Highway 20, 320 km. west of Williams Lake, 140 km east of Bella Coola.

One major industry of Anahim Lake is forestry. This industry has been hurt by the pine beetle epidemic sweeping through Western Canada. In the summer of 2006, the lumber mill of Anahim Lake closed down and laid off dozens of mill workers. However, the mill has recently re-opened at half capacity. Other local industries include cattle farming, sport fishing, and mushroom picking. The area is famous for its numerous world class fresh water fishing lodges and resorts that bring in enthusiasts from around the world.

Anahim Lake is home to National Hockey League Vezina Trophy winner and Olympic gold medalist Carey Price of the Montreal Canadiens.

Anahim Lake Elementary Jr. Secondary is a public school that is part of School District #27 that serves students from Kindergarten to Grade 10. The school has been in use since it was built in 2006. The current Principal of the school is Mr. Mikal Brogan.

Anahim Lake is the namesake for the Anahim Volcanic Belt, Anahim hotspot and Anahim Peak.

Anahim Peak

Anahim Peak, sometimes mistakenly called Anaheim, is a volcanic cone in the Anahim Volcanic Belt in British Columbia, Canada, located 39 km (24 mi) northwest of Anahim Lake and 11 km (7 mi) east of Tsitsutl Peak. It was formed when the North American Plate moved over a hotspot, similar to the one feeding the Hawaiian Islands, called the Anahim hotspot. It is one of the several volcanoes in the Anahim Volcanic Belt that stands out all by itself, rising from the Chilcotin Plateau, between the Rainbow Range and the Ilgachuz Range and near the headwaters of the Dean River.

Anahim hotspot

The Anahim hotspot is a volcanic hotspot located in the West-Central Interior of British Columbia, Canada. One of the few hotspots in North America, the Anahim plume is responsible for the creation of the Anahim Volcanic Belt. This is a 300 km (190 mi) long chain of volcanoes and other magmatic features that have undergone erosion. The chain extends from the community of Bella Bella in the west to near the small city of Quesnel in the east. While most volcanoes are created by geological activity at tectonic plate boundaries, the Anahim hotspot is located hundreds of kilometres away from the nearest plate boundary.

This hotspot's existence was first proposed in the 1970s by three scientists who used John Tuzo Wilson's classic hotspot theory. This theory proposes that a single, fixed mantle plume builds volcanoes that then, cut off from their source by the movement of the North American Plate, become increasingly inactive and eventually erode over millions of years. A more recent theory, published in 2001 by the Geological Society of America, suggests that the Anahim hotspot might be supplied by a mantle plume from the upper mantle rather than a deep-seated plume proposed by Wilson. The plume has since been tomographically imaged, showing it to be roughly 400 km (250 mi) deep. This measurement, however, could be an underestimate as the plume might originate deeper within Earth.

Volcanism as early as 14.5 million years ago has been linked to the Anahim hotspot, with the latest eruption having taken place in the last 8,000 years. This volcanic activity has produced rocks that show a bimodal distribution in composition. While these rocks were being deposited, the hotspot coincided with periods of crustal extension and uplift. Activity in modern times has been limited to earthquakes and volcanic gas emissions.

Baldface Mountain

Baldface Mountain is a conical butte-like summit in the West-Central Interior of British Columbia, Canada. It is east of Itcha Lake and northeast of the community of Anahim Lake.This mountain is a volcanic cone consisting of trachyte and phonolite. Polygenetic in nature, it was active 2.52 to 2.37 million years ago.

Bella Bella and Gale Passage dike swarms

The Bella Bella and Gale Passage dike swarms are two parallel dike swarms on the Central Coast of British Columbia, Canada. They range in age from 14.5 to 12.5 million years old. They are both chemically bimodal, consisting of rocks such as basalt, trachyte and comendite. They form the westernmost extent of the Anahim Volcanic Belt on Athlone Island, Dufferin Island and Denny Island.The Bella Bella and Gale Passage dike swarms are petrographically similar to the shield complexes in the central Anahim Volcanic Belt. As a result, the swarms are thought to represent the roots of a peralkaline magma system in which they are the magma conduits connecting the underlying magma chamber to the volcanic centre at the surface, which has been extensively eroded to remnants of eruptive breccia.

Clisbako Caldera Complex

The Clisbako Caldera Complex (also called the Cheslatta Caldera Complex) is a large dissected caldera complex in the Chilcotin Group and Anahim Volcanic Belt in central British Columbia, Canada. It has a diameter of 60 km (37 mi) and is composed mainly of Eocene felsic and mafic volcanic rocks. Rocks within the caldera range in composition from basalt to rhyolite.

Far Mountain

Far Mountain is the highest of over 13 peaks in the Ilgachuz Range in the Anahim Volcanic Belt in British Columbia, Canada. The Ilgachuz Range is one of the three major shield volcanoes that formed the Anahim Volcanic Belt when the North American Plate moved over a hotspot (the Anahim hotspot). This is similar to the one which feeds the Hawaiian Islands. The mountain is located in the western part of Itcha Ilgachuz Provincial Park.

Ilgachuz Range

The Ilgachuz Range is a name given to an extinct shield volcano in British Columbia, Canada. It is not a mountain range in the normal sense, because it was formed as a single volcano that has been eroded for the past 5 million years. It lies on the Chilcotin Plateau, located some 350 kilometres (220 mi) north-northwest of Vancouver and 30 km north of Anahim Lake. The highest peak of the range is Far Mountain. The range supports a unique grassland ecosystem. This type of grassland has not been seen anywhere else in central and southern British Columbia. The climate is cool and dry; typical of higher elevations of the Interior Plateau.

The 280 kilometres (174 mi) long West Road River rises in the Ilgachuz Range and flows east to its confluence with the Fraser River between Prince George and Quesnel. It drains an area of approximately 12,000 km2 and loses over 900 m elevation before joining the Fraser.

Itcha Mountain

Itcha Mountain is one of the two named volcanic peaks of the Itcha Range, which is located in the Chilcotin District of the Central Interior of British Columbia, Canada. It is in the Anahim Volcanic Belt, which formed when the North American Plate moved over a hotspot, similar to the one feeding the Hawaiian Islands. The Anahim Volcanic Belt includes other immediately nearby ranges, the Rainbow and Ilgachuz Ranges. Itcha Mountain is located 42 km (26 mi) northeast of Anahim Lake and 2 km (1 mi) northeast of Mount Downton, another peak of the Itcha Range. Both of these peaks are located within Itcha Ilgachuz Provincial Park, as is Far Mountain, the park's highest peak.

This mountain is the namesake for the Itcha Range, which is one of the several large shield volcanoes that stands all by itself.

King Island Pluton

The King Island Pluton is a mid-to-late Miocene intrusion of syenite and alkali granite on the Central Coast of British Columbia, Canada. It is over 20 km (12 mi) long and 2.5 km (1.6 mi) wide, extending from King Island in the west to the mainland in the east. The pluton is exposed in 1,000 m (3,300 ft) cliffs along the Dean and Burke channels west of Bella Coola.The King Island Pluton is petrographically similar to the shield complexes in the central Anahim Volcanic Belt. As a result, the pluton is thought to represent the magma chamber of an extinct volcanic centre that has since eroded away. At the time of its formation, the pluton was emplaced 2 to 5 km (1.2 to 3.1 mi) below the surface.

Mount Downton

Mount Downton is the highest summit of the 10 km (6 mi) diameter Itcha Range, located 40 km (25 mi) northeast of Anahim Lake and 33 km (21 mi) east of Far Mountain in the Chilcotin District of the Central Interior of British Columbia, Canada. It lies within Itcha Ilgachuz Provincial Park.

Mount MacKenzie

Mount MacKenzie is a volcanic peak, located 40 km (25 mi) northeast of Hagensborg, British Columbia, Canada. It is one of the volcanic peaks of the Rainbow Range, which is one of the three major shield volcanoes that form the Anahim Volcanic Belt. Mount MacKenzie was formed when the North American Plate moved over a hotspot, similar to the one feeding the Hawaiian Islands, known as the Anahim hotspot.

Nazko Cone

Nazko Cone is a small potentially active basaltic cinder cone in central British Columbia, Canada, located 75 km west of Quesnel and 150 kilometers southwest of Prince George. It is considered the easternmost volcano in the Anahim Volcanic Belt. The small tree-covered cone rises 120 m above the Chilcotin-Nechako Plateau and rests on glacial till. It was formed in three episodes of activity, the first of which took place during the Pleistocene interglacial stage about 340,000 years ago. The second stage produced a large hyaloclastite scoria mound erupted beneath the Cordilleran Ice Sheet during the Pleistocene. Its last eruption produced two small lava flows that traveled 1 km to the west, along with a blanket of volcanic ash that extends several km to the north and east of the cone.

Rainbow Range (Chilcotin Plateau)

The Rainbow Range, formerly known as the Rainbow Mountains, is a mountain range in British Columbia, Canada, located 40 kilometres (25 mi) northwest of Anahim Lake. Located on the western edge of the Chilcotin Plateau, the range adjoins the Coast Mountains Pacific Ranges to the south, and the Kitimat Ranges to the north. In some classification systems it is considered part of the Coast Mountains. It lies north of the Bella Coola and Atnarko Rivers and south and west of the Dean River, which curves around its north flank, and is relatively drier in climate and easier of terrain than more mountainous areas immediately west.

Once called Tsitsutl, meaning "rainbow mountains" in the Ulkatcho dialect of the Carrier language, that name is now the name of the range's highest peak.

Satah Mountain

Satah Mountain is a cinder cone, located 35 km (22 mi) east-northeast of Nimpo Lake in central British Columbia, Canada. It areas to the south form a N-S-trending chain of cinder cones of Pleistocene and Holocene age. It lies on the Chilcotin Plateau.

Satah Mountain occupies the high point of the Satah Mountain volcanic field. This consists of a long ridge of trachytic lava domes and flows and basaltic and trachybasaltic cinder cones that extend south from the felsic Itcha Range volcanic complex.

Satah Mountain volcanic field

The Satah Mountain volcanic field (SMVF) is an extensive north-south trending volcanic chain in the Central Interior of British Columbia that stretches south of the Itcha Range shield volcano to northeast of Nimpo Lake. The chain is located on the Chilcotin Plateau, a major subdivision of the Interior Plateau that includes other nearby volcanic features. It forms a segment of the east-west trending Anahim Volcanic Belt, whose volcanic activity ranges in age from Miocene-to-Holocene. Volcanic features in the Satah Mountain field include lava domes, cinder cones and lava flows. Its name originates from Satah Mountain, the highest volcano, located 35 km (22 mi) northeast of Nimpo Lake.Lava domes and flows are composed of trachyte and the cinder cones consist of basaltic and trachybasaltic lava. The most recently formed cone is well preserved and might have a similar age to the 7,200‑year‑old Nazko Cone at the easternmost end of the Anahim Volcanic Belt. However, recent (2015) argon-argon dating by Kuehn et al. found that the youngest SMVF feature was a 1.43 million year old plug of basaltic trachyandesite.

Tsitsutl Peak

Tsitsutl Peak is the highest volcanic peak of the Rainbow Range in British Columbia, Canada, located within Tweedsmuir South Provincial Park, 43 km (27 mi) northwest of Anahim Lake and 44 km (27 mi) northeast of Thunder Mountain.

Whitetop Mountain (British Columbia)

Whitetop Mountain is a forested hill in the West-Central Interior of British Columbia, Canada. It is on the northwest side of junction of the Chilcotin River and Downton Creek. Whitetop is a volcanic cone of the Chilcotin Plateau and Anahim Volcanic Belt.

Topics of the Anahim Volcanic Belt


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