Squamish volcanic field
Encyclopedia
The Squamish volcanic field is a small north-south trending volcanic field
on the South Coast
of British Columbia
, Canada
. It extends for only about 3 km (1.9 mi) from the eastern side of Howe Sound
northeast of Britannia Beach
to the heavily forested slope on the western side of the Squamish River
mouth. It forms the southernmost end of the Garibaldi Volcanic Belt
, the Canadian portion of the Cascade Volcanic Arc
. Its volcanoes are relatively minor to the more voluminous stratovolcano
es found throughout the Garibaldi Belt and are composed of dacite
and lesser basaltic andesite
. The field gets its name from the nearby community of Squamish
at the north end of Howe Sound on the Sea to Sky Highway.
Volcanism in the Squamish field has constructed at least two volcanic zones known as the Watts Point volcanic centre
and Monmouth Creek complex
. The most recent eruptive activity at these volcanoes is likely Pleistocene
in age and are both likely products of glaciovolcanism
during the last glacial period.
Volcanic field
A volcanic field is an area of the Earth's crust that is prone to localized volcanic activity. They usually contain 10 to 100 volcanoes, such as cinder cones and are usually in clusters. Lava flows may also occur...
on the South Coast
British Columbia Coast
The British Columbia Coast or BC Coast is Canada's western continental coastline on the Pacific Ocean. The usage is synonymous with the term West Coast of Canada....
of British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. It extends for only about 3 km (1.9 mi) from the eastern side of Howe Sound
Howe Sound
Howe Sound is a roughly triangular sound, actually a network of fjords situated immediately northwest of Vancouver.-Geography:Howe Sound's mouth at the Strait of Georgia is situated between West Vancouver and the Sunshine Coast. The sound is triangular shaped, open on its southeast towards the...
northeast of Britannia Beach
Britannia Beach, British Columbia
Britannia Beach is a small unincorporated community in the Squamish-Lillooet Regional District located approximately 30 kilometers north of Vancouver, British Columbia on the Sea-to-Sky Highway on Howe Sound. It has a population of about 300....
to the heavily forested slope on the western side of the Squamish River
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:...
mouth. It forms the southernmost end of the Garibaldi Volcanic Belt
Garibaldi Volcanic Belt
The Garibaldi Volcanic Belt, also called the Canadian Cascade Arc, 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...
, the Canadian portion of the Cascade Volcanic Arc
Cascade Volcanoes
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 mi ...
. Its volcanoes are relatively minor to the more voluminous stratovolcano
Stratovolcano
A stratovolcano, also known as a composite volcano, is a tall, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions...
es found throughout the Garibaldi Belt and are composed of dacite
Dacite
Dacite is an igneous, volcanic rock. It has an aphanitic to porphyritic texture and is intermediate in composition between andesite and rhyolite. The relative proportions of feldspars and quartz in dacite, and in many other volcanic rocks, are illustrated in the QAPF diagram...
and lesser basaltic andesite
Basaltic andesite
Basaltic andesite is a black volcanic rock containing about 55% silica. Minerals in basaltic andesite include olivine, augite and plagioclase. Basaltic andesite can be found in volcanoes around the world, including in Central America and the Andes of South America. Basaltic andesite is common in...
. The field gets its name from the nearby community of Squamish
Squamish, British Columbia
Squamish is a community and a district municipality in the Canadian province of British Columbia, located at the north end of Howe Sound on the Sea to Sky Highway...
at the north end of Howe Sound on the Sea to Sky Highway.
Volcanism in the Squamish field has constructed at least two volcanic zones known as the Watts Point volcanic centre
Watts Point volcanic centre
The Watts Point volcanic centre is a small outcrop of Pleistocene age volcanic rock at Watts Point in British Columbia, Canada, about south of Squamish and north of Vancouver, and just north of Britannia Beach. It is the southernmost volcanic zone in the Squamish volcanic field and of the...
and Monmouth Creek complex
Monmouth Creek complex
The Monmouth Creek complex is a volcanic complex in southwestern British Columbia, Canada, located southwest of the community of Squamish on the west side of the Squamish River mouth...
. The most recent eruptive activity at these volcanoes is likely Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
in age and are both likely products of glaciovolcanism
Glaciovolcanism
Glaciovolcanism is a term used to describe volcanism and related phenomena associated with glacial ice. The ice commonly constrains the erupted material and melts to create meltwater. Considerable melting of glacial ice can create massive lahars and glacial outburst floods known as jökulhlaups...
during the last glacial period.