Anahim Volcanic Belt
Encyclopedia
Volcanic belt
A volcanic belt is a large volcanically active region. Other terms are used for smaller areas of activity, such as volcanic fields. Volcanic belts are found above zones of unusually high temperature where magma is created by partial melting of solid material in the Earth's crust and upper mantle....
, stretching from just north of Vancouver Island
Vancouver Island
Vancouver Island is a large island in British Columbia, Canada. It is one of several North American locations named after George Vancouver, the British Royal Navy officer who explored the Pacific Northwest coast of North America between 1791 and 1794...
to near Quesnel
Quesnel, British Columbia
-Demographics:Quesnel had a population of 9,326 people in 2006, which was a decrease of 7.1% from the 2001 census count. The median household income in 2005 for Quesnel was $54,044, which is slightly above the British Columbia provincial average of $52,709....
, British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. 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 (0.78740157480315 in) to 3.3 cm (1.3 in) a year. The Nazko Cone
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...
, 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
North American Plate
The North American Plate is a tectonic plate covering most of North America, Greenland, Cuba, Bahamas, and parts of Siberia, Japan and Iceland. It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust...
sliding westward over a long-lived center of upwelling magma
Magma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...
called the Anahim hotspot
Anahim hotspot
The Anahim hotspot is a volcanic hotspot in central British Columbia, Canada. It is situated on the Interior Plateau, a large region that lies between the Cariboo and Monashee Mountains to the east, and the Hazelton Mountains, Coast Mountains and Cascade Range to the west...
. The hotspot is thought to be similar to the one feeding the Hawaiian Islands
Hawaiian Islands
The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...
.
Future volcanism is most likely in the form of basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
ic cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...
s, but eruptions of less mafic
Mafic
Mafic is an adjective describing a silicate mineral or rock that is rich in magnesium and iron; the term is a portmanteau of the words "magnesium" and "ferric". Most mafic minerals are dark in color and the relative density is greater than 3. Common rock-forming mafic minerals include olivine,...
magma, typical of the eastern portions of the belt, cannot be ruled out. A series of earthquakes began October 9th, 2007 in the vicinity of Nazko Cone which was related to intense subterraenean volcanic activity in the area.
The volcanic belt is defined by 37 Quaternary
Quaternary
The Quaternary Period is the most recent of the three periods of the Cenozoic Era in the geologic time scale of the ICS. It follows the Neogene Period, spanning 2.588 ± 0.005 million years ago to the present...
basalt centers and three large shield volcanoes called the Rainbow Range
Rainbow Range (Coast Mountains)
The Rainbow Range, formerly known as the Rainbow Mountains, is a mountain range in British Columbia, Canada, located northwest of Anahim Lake...
, Ilgachuz Range
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 north-northwest...
and the Itcha Range
Itcha Range
The Itcha Range is a mountain range on the Chilcotin Plateau of the West-Central Interior of British Columbia, Canada. The range is located 25 miles northeast of Anahim Lake...
. These three large volcanoes have built up dome-like piles of lava and fragmental rocks to a height of 8130 feet (2,478 m) at Tsitsutl Peak
Tsitsutl Peak
Tsitsutl Peak is the highest volcanic peak of the Rainbow Range in British Columbia, Canada, located within Tweedsmuir South Provincial Park, northwest of Anahim Lake and northeast of Thunder Mountain.-Name origin:...
in the Rainbow Range, 7873 feet (2,400 m) at Far Mountain
Far Mountain
Far Mountain is the highest of the 13 peaks of 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 . This is similar to the...
in the Ilgachuz Range, and 7760 feet (2,365 m) at Mount Downton
Mount Downton
Mount Downton is the highest summit of the diameter Itcha Range, located northeast of Anahim Lake and east of Far Mountain in the Chilcotin District of the Central Interior of British Columbia, Canada. It lies within Itcha Ilgachuz Provincial Park....
in the Itcha Range. The Rainbow Range is a low dome-like cone about 20 miles (32 km) diameter, with Anahim Peak
Anahim Peak
Anahim Peak, sometimes mistakenly called Anaheim, is a volcanic cone in the Anahim Volcanic Belt in British Columbia, Canada, located northwest of Anahim Lake and east of Tsitsutl Peak. It was formed when the North American Plate moved over a hotspot, similar to the one feeding the Hawaiian...
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
Tertiary
The Tertiary is a deprecated term for a geologic period 65 million to 2.6 million years ago. The Tertiary covered the time span between the superseded Secondary period and the Quaternary...
, pre-Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
stream
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...
erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
.
Major volcanoes of the Anahim Volcanic Belt include:
- Ilgachuz RangeIlgachuz RangeThe 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 north-northwest...
, 2410 metres (7,907 ft) - Itcha RangeItcha RangeThe Itcha Range is a mountain range on the Chilcotin Plateau of the West-Central Interior of British Columbia, Canada. The range is located 25 miles northeast of Anahim Lake...
, 2368 metres (7,769 ft) - Rainbow RangeRainbow Range (Coast Mountains)The Rainbow Range, formerly known as the Rainbow Mountains, is a mountain range in British Columbia, Canada, located northwest of Anahim Lake...
, 2478 metres (8,130 ft)
See also
- 2007–2008 Nazko earthquakes
- List of volcanoes in Canada
- Volcanism of Canada
- Volcanism of Western CanadaVolcanism of Western CanadaVolcanism of Western Canada produces lava flows, lava plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, submarine volcanoes, calderas, diatremes and maars, along with examples of more less common volcanic forms such as tuyas and subglacial mounds.-Volcanic belts:*Anahim...
- Northern Cordilleran Volcanic ProvinceNorthern Cordilleran volcanic provinceThe Northern Cordilleran Volcanic Province , formerly known as the Stikine Volcanic Belt, is a geologic province defined by the occurrence of Miocene to Holocene volcanoes in the Pacific Northwest of North America...
- Garibaldi Volcanic BeltGaribaldi Volcanic BeltThe Garibaldi Volcanic Belt, also called the Canadian Cascade Arc, is a northwest-southeast trending volcanic chain in the Pacific Ranges of the Coast Mountains that extends from Watts Point in the south to the Ha-Iltzuk Icefield in the north. This chain of volcanoes is located in southwestern...
- Chilcotin Group
- Wells Gray-Clearwater volcanic fieldWells Gray-Clearwater volcanic fieldThe Wells Gray-Clearwater volcanic field, also called the Clearwater Cone Group, is a potentially active monogenetic volcanic field in east-central British Columbia, Canada, located approximately north of Kamloops. It is situated in the Cariboo Mountains of the Columbia Mountains and on the...