The Coast Mountains are a major mountain range in the Pacific Coast Ranges of western North America, extending from southwestern Yukon through the Alaska Panhandle and virtually all of the Coast of British Columbia south to the Fraser River. The mountain range's name derives from its proximity to the sea coast, and it is often referred to as the Coast Range. The range includes volcanic and non-volcanic mountains and the extensive ice fields of the Pacific and Boundary Ranges, and the northern end of the volcanic system known as the Cascade Volcanoes. The Coast Mountains are part of a larger mountain system called the Pacific Coast Ranges or the Pacific Mountain System, which includes the Cascade Range, the Insular Mountains, the Olympic Mountains, the Oregon Coast Range, the California Coast Ranges, the Saint Elias Mountains and the Chugach Mountains. The Coast Mountains are also part of the American Cordillera—a Spanish term for an extensive chain of mountain ranges—that consists of an almost continuous sequence of mountain ranges that form the western backbone of North America, Central America, South America and Antarctica.
A tuya is a type of distinctive, flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are somewhat rare worldwide, being confined to regions which were covered by glaciers and had active volcanism during the same period.
The Northern Cordilleran Volcanic Province (NCVP), 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. This belt of volcanoes extends roughly north-northwest from northwestern British Columbia and the Alaska Panhandle through Yukon to the Southeast Fairbanks Census Area of far eastern Alaska, in a corridor hundreds of kilometres wide. It is the most recently defined volcanic province in the Western Cordillera. It has formed due to extensional cracking of the North American continent—similar to other on-land extensional volcanic zones, including the Basin and Range Province and the East African Rift. Although taking its name from the Western Cordillera, this term is a geologic grouping rather than a geographic one. The southmost part of the NCVP has more, and larger, volcanoes than does the rest of the NCVP; further north it is less clearly delineated, describing a large arch that sways westward through central Yukon.
Hoodoo Mountain is a potentially active flat-topped stratovolcano in the Stikine Country of northwestern British Columbia, Canada, located 74 km (46 mi) northeast of Wrangell, Alaska, on the north side of the lower Iskut River and 30 km (19 mi) east of its junction with the Stikine River. It is situated in the Boundary Ranges of the Coast Mountains and existed since the Late Pleistocene stage of the Pleistocene epoch, which began 130,000 years ago and ended 10,000 years ago.
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.
The Spectrum Range, formerly called the Spectrum Mountains and the Rainbow Mountains, is a subrange of the Tahltan Highland in the Stikine Country of northwestern British Columbia, 20 km west of the Stewart-Cassiar Highway, south of Mount Edziza and north of the Arctic Lake Plateau. The Spectrum Range falls within Mount Edziza Provincial Park. The range is lightly glaciated, as compared to the other ranges to the west. It is accessible only by foot or via helicopter; there are no roads to the range.
Mathews Tuya is a tuya in northcentral British Columbia. It is one of the six tuyas close to Tuya Lake. It has been partly glaciated and Ar-Ar geochronology shows that is it about 730,000 years old. It mainly comprises palagonitized tephra but also has a few dykes and jointed lava flows on its flanks. The top still has flat-lying lava flows erupted after the tephra pile grew above the surface of the enclosing lake. The other volcanoes in the area include Tuya Butte, South Tuya and Ash Mountain. The volcanoes in the region form part of the Northern Cordilleran Volcanic Province.
Kawdy Mountain is a subglacial mound on the Kawdy Plateau, the northernmost sub-plateau of the Stikine Plateau in northwestern British Columbia, Canada. It consists of nearly horizontal beds of basaltic lava, capping outward dipping beds of fragmental volcanic rocks and last erupted in Pleistocene. Kawdy Mountain is one of many basaltic volcanic features of the Stikine Volcanic Belt, which is forming because the North American tectonic plate is stretching slightly as it moves to the west.
Level Mountain is a massive complex volcano 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 2,166 m (7,106 ft), it is the third highest of five large complexes in an extensive north-south trending volcanic zone. 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 large 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 volcano. Meszah Peak is the only named peak in the Level Mountain Range.
Toozaza Peak is a tuya in the Stikine Ranges of the Cassiar Mountains in northern British Columbia, Canada, located in the Iverson Creek. Toozaza Peak is the summit of a north-south aligned ridge between the head of Toozaza Creek and the head of the Jennings River, just south of the Jennings' divide with the Little Rancheria River headwaters. The Little Rancheria and Toozaza Creek are part of the Liard, while the Jennings is part of the Yukon River drainage via Teslin Lake, and the peak therefore stands astride the line of the Continental Divide. It is part of the Tuya Volcanic Field, a volcanic field associated with the Stikine Volcanic Belt, part of the Northern Cordilleran Volcanic Province.
Volcanology of Canada includes 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. It has a very complex volcanological history spanning from the Precambrian eon at least 3.11 billion years ago when this part of the North American continent began to form.
The Stikine Plateau is a plateau in northern British Columbia, Canada. It lies between the Boundary Ranges of the Coast Mountains on the west and southwest and the Cassiar Mountains along its northeast, and between the Skeena Mountains on its south and southeast and the Jennings and Nakina Rivers on the north.
The Jennings River is a river in far northern British Columbia, Canada. It is approximately 150 kilometres (93 mi) long. The river was named for William T. Jennings (1846-1906), a civil engineer who, in 1897, assessed various road and railroad routes from the Pacific Ocean to the Yukon.
The Tanzilla Plateau is a plateau in the Stikine Country of the Northern Interior of British Columbia, Canada. It is a sub-plateau of the Stikine Plateau and is located east of the Tuya River, north of the Stikine River and surrounding Dease Lake; its eastern extremity verges on the Stikine Ranges of the Cassiar Mountains at Dark Mountain and Pyramid Mountain. The Spatsizi Plateau is to the southeast, the Klastline Plateau to the south, the Tahltan Highland to the west and southwest, and the Kawdy Plateau to the west and northwest. All are also sub-plateaus of the Stikine Plateau.
The Cottonwood River is a tributary of the Dease River in the Cassiar Country of the Northern Interior of British Columbia, Canada. Rising in the northern Stikine Ranges just east of Toozaza Peak, and just south of the origins of the Jennings and Little Rancheria River near the border with Yukon, it flows south along the east flank of the Tuya Range to meet the Dease just north of that river's source at Dease Lake, between the north end of that lake and McDame Creek and the former mining centre and community of McDame Post.
The Volcano, also known as Lava Fork volcano, is a small cinder cone in the Boundary Ranges of the Coast Mountains in northwestern British Columbia, Canada. It is located approximately 60 km (40 mi) northwest of the small community of Stewart near the head of Lava Fork. With a summit elevation of 1,656 m (5,433 ft) and a topographic prominence of 311 m (1,020 ft), it rises above the surrounding rugged landscape on a remote mountain ridge that represents the northern flank of a glaciated U-shaped valley.
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.
