Plinth Peak | |
---|---|
Highest point | |
Elevation | 2,677 m (8,783 ft) [1] |
Prominence | 947 m (3,107 ft) [1] |
Coordinates | 50°38′42.7″N123°30′38.9″W / 50.645194°N 123.510806°W |
Geography | |
Location | British Columbia, Canada |
District | Lillooet Land District |
Parent range | Pacific Ranges |
Topo map | NTS 92J12 Mount Dalgleish |
Geology | |
Rock age | Pleistocene |
Mountain type | Stratovolcano |
Volcanic arc/belt | Canadian Cascade Arc Garibaldi Volcanic Belt |
Last eruption | Pleistocene |
Climbing | |
First ascent | 1931 N. Carter; A. Dalgleish; T. Fyles; M. Winram [1] |
Easiest route | rock/ice climb |
Plinth Peak, sometimes called Plinth Mountain, is the highest satellite cone of the Mount Meager massif, and one of four overlapping volcanic cones which together form a large volcanic complex in the Garibaldi Volcanic Belt of the Canadian Cascade Arc. It is one of the most recently formed volcanic formations of the Mount Meager massif.
Plinth Peak is the highest volcanic peak of the Mount Meager massif. Located on the steep north flank of Plinth is the remnant of an inner crater wall that was destroyed by a lateral blast during a period of volcanic activity about 2,350 years ago.[ citation needed ]
The Garibaldi Volcanic Belt 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 British Columbia, Canada. It forms the northernmost segment of the Cascade Volcanic Arc, which includes Mount St. Helens and Mount Baker. Most volcanoes of the Garibaldi chain are dormant stratovolcanoes and subglacial volcanoes that have been eroded by glacial ice. Less common volcanic landforms include cinder cones, volcanic plugs, lava domes and calderas. These diverse formations were created by different styles of volcanic activity, including Peléan and Plinian eruptions.
The Pacific Ranges are the southernmost subdivision of the Coast Mountains portion of the Pacific Cordillera. Located entirely within British Columbia, Canada, they run northwest from the lower stretches of the Fraser River to Bella Coola and Burke Channel, north of which are the Kitimat Ranges. The Coast Mountains lie between the Interior Plateau and the Coast of British Columbia.
The Mount Meager massif is a group of volcanic peaks in the Pacific Ranges of the Coast Mountains in southwestern British Columbia, Canada. Part of the Cascade Volcanic Arc of western North America, it is located 150 km (93 mi) north of Vancouver at the northern end of the Pemberton Valley and reaches a maximum elevation of 2,680 m (8,790 ft). The massif is capped by several eroded volcanic edifices, including lava domes, volcanic plugs and overlapping piles of lava flows; these form at least six major summits including Mount Meager which is the second highest of the massif.
Mount Silverthrone, officially named Silverthrone Mountain, is a mountain in the Pacific Ranges of the Coast Mountains of British Columbia, Canada, located over 320 km (200 mi) northwest of the city of Vancouver and about 50 km (30 mi) west of Mount Waddington, British Columbia, Canada. It is the highest peak in the Ha-Iltzuk Icefield, which is the largest icefield in the Coast Mountains south of the Alaska Panhandle.
The Cascade Volcanoes are a number of volcanoes in a volcanic arc in western North America, extending from southwestern British Columbia through Washington and Oregon to Northern California, a distance of well over 700 miles (1,100 km). The arc formed due to subduction along the Cascadia subduction zone. Although taking its name from the Cascade Range, this term is a geologic grouping rather than a geographic one, and the Cascade Volcanoes extend north into the Coast Mountains, past the Fraser River which is the northward limit of the Cascade Range proper.
Devastator Peak, also known as The Devastator, is the lowest and southernmost of the six subsidiary peaks that form the Mount Meager massif in southwestern British Columbia, Canada. It is located 55 km (34 mi) west of Bralorne.
Mount Job is one of six named volcanic peaks of the Mount Meager massif in British Columbia, Canada. It is a pile of rubble held together by volcanic ash and sand. The main summit of Mount Job is hard to climb because of difficult access and its horribly loose rock.
Capricorn Mountain is one of the several volcanic peaks of the Mount Meager massif in southwestern British Columbia, Canada. Its slopes appear to be more gentle than those of the massif's other volcanic peaks. The mountain consists of a boomerang-shaped ridge, with one summit at each end and the main summit in the centre.
The Pemberton Volcanic Belt is an eroded Oligocene-Miocene volcanic belt at a low angle near the Mount Meager massif, British Columbia, Canada. The Garibaldi and Pemberton volcanic belts appear to merge into a single belt, although the Pemberton is older than the Garibaldi Volcanic Belt. The Pemberton Volcanic Belt is one of the geological formations comprising the Canadian Cascade Arc. It formed as a result of subduction of the former Farallon Plate.
Pylon Peak is the southernmost of six named volcanic peaks comprising the Mount Meager massif in British Columbia, Canada. Two pinnacled ridges extend from Pylon and are named respectively the Pylons and the Marionettes. Pylon Peak overlooks the Meager Creek Hot Springs.
The geology of the Pacific Northwest includes the composition, structure, physical properties and the processes that shape the Pacific Northwest region of North America. The region is part of the Ring of Fire: the subduction of the Pacific and Farallon Plates under the North American Plate is responsible for many of the area's scenic features as well as some of its hazards, such as volcanoes, earthquakes, and landslides.
The Silverthrone Caldera is a potentially active caldera complex in southwestern British Columbia, Canada, located over 350 kilometres (220 mi) northwest of the city of Vancouver and about 50 kilometres (31 mi) west of Mount Waddington in the Pacific Ranges of the Coast Mountains. The caldera is one of the largest of the few calderas in western Canada, measuring about 30 kilometres (19 mi) long (north-south) and 20 kilometres (12 mi) wide (east-west). Mount Silverthrone, an eroded lava dome on the caldera's northern flank that is 2,864 metres (9,396 ft) high, may be the highest volcano in Canada.
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.
The Plinth Assemblage, also known as the Plinth Formation, is an accreted terrane of igneous rocks in southwestern British Columbia, Canada, located just north of the Lillooet River and on the northern flank of the Mount Meager massif. It is named after Plinth Peak, a peak made of Plinth Assemblage rocks.
The Devastator Assemblage is a geological formation comprising a portion of the Mount Meager massif in southwestern British Columbia, Canada. It is named after Devastator Peak, the lowest and southernmost subsidiary peak of Meager. The south and west flanks of Pylon Peak and Devastator Peak are made of The Devastator Assemblage rocks.
The Mosaic Assemblage is a rock unit of the Pacific Ranges of the Coast Mountains in southwestern British Columbia, Canada. It is the namesake of Mosaic Glacier, which is drained by Mosaic Creek. This geological formation formed 140,000 to less than 90,000 years ago when porphyritic plagioclase-augite-olivine basalt and trachybasalt was erupted in valleys and on mountain ridges. These volcanic rocks form scoriaceous lava flows, breccias, volcanic bombs and pillow lavas.
The Job Assemblage is a geological formation comprising a portion of the Mount Meager massif in southwestern British Columbia, Canada. It is named after Mount Job, a subsidiary peak of Meager. The rock unit was formed during a period of rhyodacite volcanism during the Pleistocene epoch.
The Capricorn Assemblage, also known as the Capricorn Formation, is a geological formation comprising the central portion of the Mount Meager massif in southwestern British Columbia, Canada. It is named after Capricorn Mountain, the third highest subsidiary peak of Meager. The assemblage was formed during a period of volcanic activity about or less than 90,000 years ago.
The Pylon Assemblage is an accreted terrane of igneous rocks in southwestern British Columbia, Canada, located about 150 km (93 mi) north of Vancouver. It is named after Pylon Peak, a summit of the Mount Meager massif. Two units make up the Pylon Assemblage, although the youngest unit comprises nearly 100% of the assemblage.
The Bridge River Vent is a volcanic crater in the Pacific Ranges of the Coast Mountains in southwestern British Columbia, Canada. It is located 51 km (32 mi) west of Bralorne on the northeastern flank of the Mount Meager massif. With an elevation of 1,524 m (5,000 ft), it lies on the steep northern face of Plinth Peak, a 2,677 m (8,783 ft) high volcanic peak comprising the northern portion of Meager. The vent rises above the western shoulder of the Pemberton Valley and represents the northernmost volcanic feature of the Mount Meager massif.