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29-857: The Garibaldi Ranges are the next-to-southwesternmost subdivision of the Pacific Ranges of the Coast Mountains ; only the North Shore Mountains are farther southwest. They lie between the valley formed by the pass between the Cheakamus River and Green River on the west (the location of the Resort Municipality of Whistler ) and the valley of the Lillooet River on the east, and extend south into Maple Ridge , an eastern suburb of Vancouver , and

58-733: A full listing of rivers in the Pacific Ranges, see List of rivers of the Pacific Ranges . Coast Plutonic Complex The Coast Range Arc was a large volcanic arc system, extending from northern Washington through British Columbia and the Alaska Panhandle to southwestern Yukon . The Coast Range Arc lies along the western margin of the North American Plate in the Pacific Northwest of western North America . Although taking its name from

87-553: A glittering medium-grade metamorphic rock called schist . The older intrusions of the Coast Range Arc were then deformed under the heat and pressure of later intrusions, turning them into a layered metamorphic rock known as gneiss . In some places, mixtures of older intrusive rocks and the original oceanic rocks have been distorted and warped under intense heat, weight and stress to create unusual swirled patterns known as migmatite , appearing to have been nearly melted in

116-571: A large ski resort at Whistler , most of the land in the range is completely undeveloped. Historically, in the southern part of the range, mining was important at various times in the Lillooet, Bridge River and Squamish areas, and large pulp and paper mills at Powell River, Port Mellon and Woodfibre. The largest hydroelectric development in the Pacific Ranges is the Bridge River Power Project , though smaller hydro plants are on

145-536: A result of the North American Plate sliding over a place that has experienced active volcanism for a long period of time which is described as the Anahim hotspot . During its formation, it lay beneath granitic intrusions of the Coast Range Arc. The approximately 20-kilometre (12 mi) long Bella Bella and approximately 6-kilometre (4 mi) long Gale Passage dike swarms lie in granitic intrusions of

174-905: Is usually referred to as the Coast Plutonic Complex or the Coast Mountains Batholith . It is a coast-parallel continental volcanic arc similar to the Andes of South America and the largest continental volcanic arc fossil in the world. Volcanism in the arc began during the Late Cretaceous period 100 million years ago based on andesitic composition of the Early Cretaceous volcanic sections and their close temporal and spatial association with masses of felsic intrusive igneous rock with phaneritic texture called tonalite . The basement of

203-818: The Coast Mountains , this term is a geologic grouping rather than a geographic one, and the Coast Range Arc extended south into the High Cascades of the Cascade Range , past the Fraser River which is the northward limit of the Cascade Range proper. The Coast Range Arc formed as a result of subduction of the Kula and pre-existing Farallon Plates . It is most famous for being the largest single body of granitic rock in North America, which

232-485: The Silverthrone Caldera , which lie 140 and 190 km northwest of the main volcanic belt. The Cascadia subduction zone is a 680 mi (1,094 km) long fault , running 50 mi (80 km) off the west-coast of the Pacific Northwest from northern California to Vancouver Island . The plates move at a relative rate of over 0.4 inches (10 mm) per year at a somewhat oblique angle to

261-507: The Waddington Range these are also considered to be " ranges " but are listed separately here because of their unique character). List is incomplete Some Protected areas, recreation areas and other non-park preservation areas are not listed. Many relatively unknown rivers of considerable size along the coastal flank of the range are not listed, partly because they are largely unknown and also very difficult to access. For

290-567: The Cascade Range contributes to further obscuring the presence of a trench. However, in common with most other subduction zones, the outer margin is slowly being compressed, similar to a giant spring . When the stored energy is suddenly released by slippage across the fault at irregular intervals, the Cascadia subduction zone can create very large earthquakes , such as the 8.7–9.2 M w   Cascadia earthquake of 1700 . Many smaller ranges and subranges are not listed at present. (Other than

319-404: The Cascade Range, which is the southernmost boundary of the arc. Here, these granites intruded highly deformed ocean rocks and assorted fragments from pre-existing island arcs, largely remnants of the ancient Bridge River Ocean which lay between North America and the pre-existing Insular Islands . Massive amounts of molten granite injected over this period, burning the old oceanic sediments into

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348-555: The Coast Range Arc are intruded by widespread basaltic dikes . These dikes, although not voluminous, provide an important sampling of the post-arc lithosphere . Additionally, widespread volcanic belts , such as the Anahim Volcanic Belt , lie in the middle of the Coast Range Arc. Volcanics that form the Anahim Volcanic Belt are not strictly related to Coast Range Arc subduction, but might have formed as

377-539: The Coast Range Arc to this day are granitic intrusions , which were formed when magma intruded and cooled at depth beneath the volcanoes. However, remnants of some volcanoes exist in southwestern Yukon, including Montana Mountain , Mount Nansen , and the Bennett Lake , Mount Skukum and Sifton Range volcanic complexes . Many granitic rocks of the Coast Range Arc are plentiful in the North Cascades of

406-475: The Coast Range Arc was likely Early Cretaceous and Late Jurassic intrusions. Stratigraphic and field relations in the arc suggest that the Coast Range Arc was created on Stikinia , a geologic feature that formed in an older volcanic arc environment during the Paleozoic and Mesozoic periods. One of the major events during the Coast Range Arc was about 85 million years ago when a huge rift developed near

435-610: The Kula Plate began subducting underneath Alaska and southwestern Yukon at the northern end of the arc during the early Eocene period. The Coast Range Arc was home to some of the world's most dangerous and explosive volcanoes. Cataclysmic eruptions at the British Columbia–Yukon border created a huge nested caldera called the Bennett Lake Volcanic Complex about 50 million years ago during

464-851: The Stave River-Alouette Lake system in Mission and Maple Ridge, the Daisy Lake-Squamish River division of the Cheakamus Powerhouse, and another power dam and power plant at Clowhom . Although the range was extensively surveyed for possible rail routes, only that of the Pacific Great Eastern (now part of CN) was eventually built; the Homathko River-Bute Inlet route, however, was one of the two main choices in

493-656: The center of the oceanic Farallon Plate . This rifting event created the oceanic Kula Plate . It is unknown why such a large rupture of the Farallon Plate occurred. Some geologists believe some fundamental change in convection within the Earth's mantle caused the rifting event, while others believe the huge oceanic plate became mechanically unstable as it continued to subduct beneath the Pacific Northwest. The Kula Plate once again continued to subduct beneath

522-540: The continental margin, supporting the Coast Range Arc. Volcanism began to decline along the length of the arc about 60 million years ago during the early Paleogene period of the Cenozoic era as the rapid northern movement of the Kula Plate became parallel with the Pacific Northwest, creating a transform fault plate boundary similar to the Queen Charlotte Fault . During this passive plate boundary,

551-653: The core of this set of ridges decorated with sharp, spiny peaks, is the highest - Mount Judge Howay 2262 m (7421 ft). The southernmost major peaks of the Garibaldi Ranges are in Golden Ears Provincial Park just north of Haney (downtown Maple Ridge ), whose cluster of sugarloafs resemble a donkey's ears and, on the day of naming, were gleaming in the sunset; the highest of these is Golden Ears at 1716 m (5630 ft). Pacific Ranges The Pacific Ranges include four of

580-518: The deliberations of the CPR's routing. The Pacific Ranges are part of the southern portion of the Coast Plutonic Complex and has been characterized by rapid rates of uplift over the past 4 million years, which has led to relatively high rates of erosion . The Garibaldi Volcanic Belt is within the Pacific Ranges, which is a volcanic belt formed by the subduction of the Juan de Fuca Plate (a remnant of

609-492: The early Eocene period. These eruptions were from vents along arcuate fracture systems associated with the caldera, which discharged about 850 cubic kilometres (200 cu mi) of pyroclastic material. This volcanic event occurred shortly before nearly all the Kula Plate had been subducted beneath the North American Plate about 40 million years ago. Since the end of the Coast Range Arc about 50 million years ago, many volcanoes have disappeared from erosion . What remains of

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638-681: The five major coastal icecaps in the southern Coast Mountains . These are the largest temperate-latitude icecaps in the world and fuel a number of very major rivers (by volume, not length). One of these contains Mount Waddington , the highest summit entirely within British Columbia . Also within this region is Hunlen Falls , among the highest in Canada , located in Tweedsmuir South Provincial Park . Other than logging and various hydroelectric developments, and

667-850: The much larger Farallon Plate ) under the North American Plate along the Cascadia subduction zone . The belt is the northern extension of the Cascade Volcanic Arc in the United States (which includes the volcanoes Mount St. Helens and Mount Baker ) and contains the most explosive young volcanoes in Canada. The eruption styles in the belt range from effusive to explosive , with compositions from basalt to rhyolite . Morphologically, centers include calderas , cinder cones , stratovolcanoes and small isolated lava masses. Due to repeated continental and alpine glaciations, many of

696-526: The northern District of Mission . To their south are the North Shore Mountains overlooking Vancouver while to their southeast are the Douglas Ranges . They take their name indirectly from Mount Garibaldi on the western side of the range, which is the namesake of Garibaldi Provincial Park . Their southern end between the upper Stave River and Pitt Lake is north of the municipality of Maple Ridge , and forms Golden Ears Provincial Park (which

725-618: The procedure. The remarkable migmatite of the Chelan and Skagit areas in Washington are well known in geologic circles. During construction of intrusions 70 and 57 million years ago, the northern motion of the Kula Plate might have been between 140 and 110 millimetres (5.5–4.3 in) per year. However, other geologic studies determined the Kula Plate moved at a rate as fast as 200 millimetres (7.9 in) per year. Intrusions of

754-458: The range, consisting mostly of Garibaldi Provincial Park , is extremely alpine in character, with large icefields and a sea of high peaks. The southern part of the range, north of Stave Lake and between the upper Pitt River and the lower Lillooet River , has no major icefields because of the precipitous character of the network of plunging U-shaped valleys - many well over 5000' deep, with individual peaks with near-vertical flanks up to 7000'. At

783-408: The subduction zone. Unlike most subduction zones worldwide, there is no oceanic trench present along the continental margin in Cascadia . Instead, terranes and the accretionary wedge have been uplifted to form a series of coast ranges and exotic mountains. A high rate of sedimentation from the outflow of the three major rivers ( Fraser River , Columbia River , and Klamath River ) which cross

812-630: The volcanic deposits in the belt reflect complex interactions between magma composition, topography, and changing ice configurations. The most recent major catastrophic eruption in the Garibaldi Volcanic Belt was from the Mount Meager massif 2,350 BP , which is Canada's most recent major catastrophic eruption. The Garibaldi Volcanic Belt contains two extra volcanic fields, the Franklin Glacier Complex and

841-431: Was originally part of Garibaldi Park ). Their most famous mountain , The Black Tusk , is not among the highest in the range; it is a volcanic plug on the meadow-ridge between Garibaldi and Cheakamus Lakes, just south of the resort of Whistler, British Columbia . The highest peak in the range is just north of the resort, Wedge Mountain 2892 m (9498 ft) a.k.a. Wedgemont and "The Wedge". The northern part of

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