The Garibaldi Lake volcanic field is a

volcanic field A volcanic field is an area of Earth's crust that is prone to localized volcanic activity. The type and number of volcanoes required to be called a "field" is not well-defined. Volcanic fields usually consist of clusters of up to 100 volcanoes ...

, located in British Columbia, Canada. It was formed by a group of nine small andesitic

stratovolcano A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and pe ...

es and

basaltic andesite Basaltic andesite is a volcanic rock that is intermediate in composition between basalt and andesite. It is composed predominantly of augite and plagioclase. Basaltic andesite can be found in volcanoes around the world, including in Central Ameri ...

vents in the scenic

Garibaldi Lake Garibaldi Lake is a turquoise-coloured alpine lake in British Columbia, Canada, located 37 km (23 mi) north of Squamish and 19 km (12 mi) south of Whistler. The lake lies within Garibaldi Provincial Park, which features moun ...

area immediately north of

Mount Garibaldi Mount Garibaldi (known as Nch'kaý to the indigenous Squamish people) 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 surroundi ...

was formed during the late

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

and early Holocene. The oldest stratovolcano, The Black Tusk, formed between about 1.3 and 1.1 million years ago ( Ma). Following glacial dissection, renewed volcanism produced the

lava dome In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions on ...

and flow forming its summit. Other Pleistocene vents are located along and to the west of the

Cheakamus River The Cheakamus River (pron. CHEEK-a-mus) is a tributary of the Squamish River, beginning on the west slopes of Outlier Peak in Garibaldi Provincial Park upstream from Cheakamus Lake on the southeastern outskirts of the resort area of Whistler. ...

Cinder Cone A cinder cone (or scoria cone) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent. The pyroclastic fragments are formed by explosive eruptions or ...

, to the east of The Black Tusk, produced a 9-km-long

lava flow Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or und ...

during the late Pleistocene or early Holocene. Mount Price, west of Garibaldi Lake, 5 km south of The Black Tusk, was formed in three stages of activity, dating back 1.1 million years, the latest of which produced two large

s from

Clinker Peak Clinker Peak is a peak on the shoulder of Mount Price in the Garibaldi Provincial Park in British Columbia, Canada. It is a stratovolcano in the Garibaldi Volcanic Belt, part of the Clinker Ridge on the west side of Garibaldi Lake. Clinker Peak ...

during the early Holocene that ponded against the retreating continental

ice sheet In glaciology, an ice sheet, also known as a continental glacier, is a mass of glacial ice that covers surrounding terrain and is greater than . The only current ice sheets are in Antarctica and Greenland; during the Last Glacial Period at L ...

and formed

The Barrier The Barrier is a lava dam retaining the Garibaldi Lake system in southwestern British Columbia, Canada. It is over thick and about long where it impounds the lake. The area below and adjacent to The Barrier is considered hazardous due to the ...

, containing Garibaldi Lake. The Table is a steep-sided andesite

tuya A tuya is a flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are rare worldwide, being confined to regions which were covered by glaciers and had active volcanism during the same period. As lava ...

, situated approximately 3 km southwest of Mount Price and south of Garibaldi Lake. It rises 305 meters above

glaciated A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as ...

basement

rock Rock most often refers to: * Rock (geology), a naturally occurring solid aggregate of minerals or mineraloids * Rock music, a genre of popular music Rock or Rocks may also refer to: Places United Kingdom * Rock, Caerphilly, a location in Wales ...

s. The tuya formed by effusion of flatlying flows within erratics on its summit and lack of

erosion Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distin ...

al features attributable to glacial suggest that The Table was also formed during the early Holocene.

is a stratovolcano on the west shoulder of Mount Price on the west side of

. It has produced two large lava flows about 9,000 years ago. Mount Brew is a

subglacial mound A subglacial mound (SUGM) is a type of subglacial volcano. This type of volcano forms when lava erupts beneath a thick glacier or ice sheet. The magma forming these volcanoes was not hot enough to melt a vertical pipe right through the overlying g ...

, which last erupted during the

Hazards

Future eruptions within the region could endanger the municipalities of Whistler and Squamish. Even though no Plinian eruptions are recognized, even

Peléan eruption Peléan eruptions are a type of volcanic eruption. They can occur when viscous magma, typically of rhyolitic or andesitic type, is involved, and share some similarities with Vulcanian eruptions. The most important characteristic of a Peléan eru ...

s may possibly create large amounts of

volcanic ash Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, created during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer ...

that will possibly affect these close by villages. Ash columns from the volcanoes might rise hundreds of metres and could make this a serious hazard for air traffic. The unstable lava formation of

has in the past unleashed several debris flows in the area below the lake, most recently in 1855-56 forming a large boulder field which gives Rubble Creek its name. Concerns about the Barrier's instability due to

volcanic A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are ...

tectonic Tectonics (; ) are the processes that control the structure and properties of the Earth's crust and its evolution through time. These include the processes of mountain building, the growth and behavior of the strong, old cores of continents k ...

, or heavy rainfall activity prompted the provincial government to declare the area immediately below it unsafe for human habitation in 1981. This led to the evacuation of the nearby village of

Garibaldi Giuseppe Maria Garibaldi ( , ;In his native Ligurian language, he is known as ''Gioxeppe Gaibado''. In his particular Niçard dialect of Ligurian, he was known as ''Jousé'' or ''Josep''. 4 July 1807 – 2 June 1882) was an Italian general, patr ...

, and the relocation of residents to new recreational subdivisions away from the hazard zone. Should the Barrier completely collapse, Garibaldi Lake would be entirely released and downstream damage in the Cheakamus and

Squamish River The Squamish River is a short but very large river in the Canadian province of British Columbia. Its drainage basin is in size. The total length of the Squamish River is approximately . Course The Squamish River drains a complex of basins in the ...

s would be considerable, including major damage to the town of Squamish and possibly an impact wave on the waters of

Howe Sound Howe Sound (french: Baie (de /d')Howe, squ, Átl'ka7tsem, Nexwnéwu7ts, Txwnéwu7ts) is a roughly triangular sound, that joins a network of fjords situated immediately northwest of Vancouver, British Columbia. It was designated as a UNESCO Biosp ...

that would reach

Vancouver Island Vancouver Island is an island in the northeastern Pacific Ocean and part of the Canadian province of British Columbia. The island is in length, in width at its widest point, and in total area, while are of land. The island is the largest by ...

External links

*{{cite gvp, name=Garibaldi Lake, vn=320190 Subduction volcanoes Pleistocene volcanism Holocene volcanism Volcanic fields of Canada

Hazards

See also

External links