Mount Garibaldi
Mount Garibaldi is a dormant stratovolcano in the Garibaldi Ranges of the Pacific Ranges in southwestern British Columbia, Canada. It has a maximum elevation of and rises above the surrounding landscape on the east side of the Cheakamus River in New Westminster Land District. In addition to the main peak, Mount Garibaldi has two named sub-peaks. Atwell Peak is a sharp, conical peak slightly higher than the more rounded peak of Dalton Dome. Both were volcanically active at different times throughout Mount Garibaldi's eruptive history. The northern and eastern flanks of Mount Garibaldi are obscured by the Garibaldi Névé, a large snowfield containing several radiating glaciers. Flowing from the steep western face of Mount Garibaldi is the Cheekye River, a tributary of the Cheakamus River. Opal Cone on the southeastern flank is a small volcanic cone from which a lengthy lava flow descends. The western face is a landslide feature that formed in a series of collapses between 12,800 and 11,500 years ago. These collapses resulted in the formation of a large debris flow deposit that fans out into the Squamish Valley.
Mount Garibaldi has been the focus of intermittent volcanic activity over the last 260,000 years. This activity produced mostly dacite, the main type of volcanic rock forming Mount Garibaldi. Volcanism between 260,000 and 220,000 years ago constructed an ancestral cone that was subsequently destroyed. Another growth period began with the eruption of Atwell Peak about 13,000 years ago when Mount Garibaldi was surrounded by an ice sheet during the last glacial period. The latest period of volcanic activity took place about 10,000 years ago with eruptions from Dalton Dome and Opal Cone after the ice sheet retreated. Although the mountain is not known to have been volcanically active since that time, it could erupt again, which could endanger the nearby populace. If this were to happen, relief efforts could be organized by teams such as the Interagency Volcanic Event Notification Plan who are prepared to notify people threatened by volcanic eruptions in Canada.
The area surrounding Mount Garibaldi has been inhabited by indigenous peoples for thousands of years. Their oral history includes a story of the mountain and a great flood. The non-indigenous name of the mountain was given by George Henry Richards in 1860 in honour of the Italian patriot and soldier Giuseppe Garibaldi. Several mountaineers had climbed Mount Garibaldi by the early 1900s, some of whom were members of mountaineering clubs. A plane operated by Pacific Western Airlines crashed on the slopes of Mount Garibaldi in 1953; all five people aboard were killed. The construction of a ski resort was begun in the late 1960s, but developments were halted in 1969 due to financial difficulties. Several climbing routes ascend the flanks of Mount Garibaldi and involve traversing glaciers, snow slopes or loose rock. Mountain climbing hazards include crevasses, avalanches and rockfalls. Access to Mount Garibaldi is via hiking trails from Alice Ridge, Brohm Ridge, and the Diamond Head parking lot at the end of Garibaldi Park Road.
Geography
Background
Mount Garibaldi is located on the east side of the Cheakamus River between Squamish and Whistler in New Westminster Land District. It lies within the Pacific Ranges Ecoregion, a mountainous region of the southern Coast Mountains characterized by high, steep and rugged mountains made of granitic rocks. Much of this ecoregion encompasses the Pacific Ranges in southwestern British Columbia, although it also includes the northwesternmost portion of the Cascade Range in Washington state. Several coastal islands, channels and fjords occur along the western margin of the Pacific Ranges Ecoregion. The Pacific Ranges Ecoregion is part of the Coast and Mountains Ecoprovince which forms part of the Humid Maritime and Highlands Ecodivision.The Pacific Ranges Ecoregion is subdivided into seven ecosections, the Eastern Pacific Ranges Ecosection being the main ecosection at Mount Garibaldi. This ecosection is characterized by a rugged landscape of mountains that increase in elevation from south to north; the northern summits contain large icefields. A transitional climate between coastal maritime and interior continental climates dominates the Eastern Pacific Ranges Ecosection. It is characterized by little precipitation and mild temperatures due to air from the Pacific Ocean often passing over this area. During winter, cold Arctic air invades from the Central Interior, resulting in extreme cloud cover and snow. A number of other volcanoes are situated within the Eastern Pacific Ranges Ecosection. This includes Mount Cayley, which lies in the Squamish River watershed, and Mount Meager, which lies near the headwaters of the Lillooet River.
Several rivers flow through the Eastern Pacific Ranges Ecosection, including the Fraser and Coquihalla rivers on its eastern side, the Cheakamus, Squamish and Elaho rivers on its western side and the Lillooet River lying in the middle. Coastal western hemlock forests dominate nearly all the valleys and lower slopes of this ecosection, the upper slopes containing subalpine mountain hemlock forests and, to a lesser extent, Engelmann spruce and subalpine fir forests. Alpine vegetation lies just above the subalpine forests, which is normally overlain by barren rock. Wildlife such as grey jays, chipmunks, squirrels, flickers, Columbian black tailed deer, mountain goats, wolverines, cougars and grizzly and black bears are locally present. The communities of Whistler, Pemberton, Mount Currie, Hope and Yale are situated within the Eastern Pacific Ranges Ecosection, all of which are connected to the Lower Mainland by a network of highways.
Subfeatures
The northern and eastern flanks of Mount Garibaldi are covered by the Garibaldi Névé, the main glacial feature at the volcano. Several individually named outlet glaciers drain the Garibaldi Névé. These include Garibaldi Glacier northwest of Opal Cone, North Pitt Glacier on the northeastern face of Mount Garibaldi, South Pitt Glacier southeast of Glacier Pikes, Lava Glacier west of Mamquam Lake, Sentinel Glacier southeast of Garibaldi Lake, Warren Glacier at the headwaters of Culiton Creek, Bishop Glacier south of the head of the Pitt River, Phoenix Glacier south of Deception Peak and Pike Glacier east of Glacier Pikes. The Garibaldi and Lava glaciers issue from the south side of the Garibaldi Névé, sending their muddy waters to the Mamquam River. Immediately to the north of Mount Garibaldi and directly below its northern face, the Warren Glacier flows towards the Cheakamus River. The Garibaldi Névé and its outlet glaciers have a combined area of about. Other glaciers on Mount Garibaldi include Cheekye Glacier south of the summit and Diamond Glacier between Atwell Peak and Diamond Head. Although the glaciers at times have seen surges reaching further down slope, a 2009 study published in the Global and Planetary Change journal found that they overall have been progressively retreating since the early 1900s. A study conducted by the University of British Columbia in 2015 determined that 70% of all the glacial ice in Canada would be melted away by the year 2100. However, observations of the nearby Helm Glacier and other glaciers throughout Canada in 2022 suggest that the 2015 estimate may be an underestimation.Mount Garibaldi contains a number of individually named peaks. Atwell Peak is a conical plug dome in elevation. It is named after Atwell Duncan Francis Joseph King, an ardent mountaineer who led the first ascent of Mount Garibaldi in 1907. Atwell Peak contains sharp and exposed ridges, as well as steep and loose faces that are prone to avalanching. Dalton Dome is a blunt summit named after Arthur Tinniswood Dalton. Dalton was a Vancouver architect, city assessor and mountaineer who took part in the first ascent of Mount Garibaldi. The eastern side of Mount Garibaldi contains a peak known as The Tent. Opal Cone on the southeastern flank of Mount Garibaldi is a parasitic cone near the south side of Garibaldi Glacier. A spur known as The Sharkin separates the Warren and North Pitt glaciers on the northeast side of Mount Garibaldi. Diamond Head is a subsidiary peak on the south side of Mount Garibaldi named for its resemblance to Diamond Head in Hawaii.
Mount Garibaldi lies within the Squamish River watershed. Its steep western face is the source of the Cheekye River which drains a small but steep catchment on its western flank that covers an area of. The Cheekye River flows west into the Cheakamus River which flows south and southwest into the Squamish River. Cheekye is a Squamish name meaning "strong rushing water". Ring Creek originates from the Bishop and Diamond glaciers on Mount Garibaldi. It flows west and southwest into the Mamquam River which flows west and south into the mouth of the Squamish River. Zig Zag Creek drains Lava Glacier and flows southeast into Skookum Creek. The Pitt River also originates at Mount Garibaldi and flows southwest from the North Pitt and South Pitt glaciers into the Fraser River.
Geology
Mount Garibaldi is one of the three principal volcanoes in the southern segment of the Garibaldi Volcanic Belt, the other two being Mount Price and The Black Tusk. It represents the largest volcano in the combined Mount Garibaldi–Garibaldi Lake volcanic field, which encompasses of volcanic material. This volcanic field consists of at least twelve eruptive centres that are in the form of stratovolcanoes, lava domes, cinder cones and subglacial volcanoes. These include Mount Price, The Black Tusk, The Table, Cinder Cone and Round Mountain, all of which formed in the last 1.3 million years. The Mount Garibaldi–Garibaldi Lake volcanic field is normally separated into the Mount Garibaldi and Garibaldi Lake volcanic fields on the basis of differing magmatic chemistry. The Mount Garibaldi lavas are hypersthene-normative hawaiites and nepheline-normative mugearite with subordinate olivine tholeiites whereas the Garibaldi Lake lavas are calc-alkaline basaltic andesites through rhyolite.Like other volcanoes in the Garibaldi Volcanic Belt, Mount Garibaldi formed as a result of subduction zone volcanism. As the Juan de Fuca Plate thrusts under the North American Plate at the Cascadia subduction zone, it forms volcanoes and volcanic eruptions.