Wells Gray-Clearwater volcanic field
Encyclopedia
The Wells Gray-Clearwater volcanic field, also called the Clearwater Cone Group, is a potentially active monogenetic volcanic field
Monogenetic volcanic field
A monogenetic volcanic field is a volcanic field of small, scattered volcanic vents. These volcanic fields, containing numerous monogenetic volcanoes, are noted for having only one short eruptive event at each volcano, as opposed to regular volcanoes that have several eruptions from the same vent...

 in east-central 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, located approximately 100 kilometres (62.1 mi) north of Kamloops
Kamloops, British Columbia
Kamloops is a city in south central British Columbia, at the confluence of the two branches of the Thompson River and near Kamloops Lake. It is the largest community in the Thompson-Nicola Regional District and the location of the regional district's offices. The surrounding region is more commonly...

. It is situated in the Cariboo Mountains
Cariboo Mountains
The Cariboo Mountains are the northernmost subrange of the Columbia Mountains, which run down into the Spokane, Washington area of the United States and include the Selkirks, Monashees and Purcells. The Cariboo Mountains are entirely within the province of British Columbia, Canada. The range is...

 of the Columbia Mountains
Columbia Mountains
The Columbia Mountains are a group of mountain ranges located in southeastern British Columbia, and partially in Montana, Idaho and Washington. The mountain range covers 135,952 km² . The range is bounded by the Rocky Mountain Trench on the east, and the Kootenay River on the south; their...

 and on the Quesnel
Quesnel Highland
The Quesnel Highland is a geographic area in the Central Interior of the Canadian province of British Columbia. As defined by BC government geographer in Landforms of British Columbia, an account and analysis of British Columbia geography that is often cited as authoritative...

 and Shuswap Highland
Shuswap Highland
The Shuswap Highland is a plateau-like hilly area of in British Columbia, Canada. It spans the upland area between the Bonaparte and Thompson Plateaus from the area of Mahood Lake, at the southeast corner of the Cariboo Plateau, southeast towards the lower Shuswap River east of Vernon in the...

s. As a monogenetic volcanic field, it is a place with numerous small basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic volcano
Volcano
2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

es and extensive lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

 flows.

Most of the Wells Gray-Clearwater volcanic field is encompassed within a large wilderness
Wilderness
Wilderness or wildland is a natural environment on Earth that has not been significantly modified by human activity. It may also be defined as: "The most intact, undisturbed wild natural areas left on our planet—those last truly wild places that humans do not control and have not developed with...

 park called Wells Gray Provincial Park
Wells Gray Provincial Park
Wells Gray Provincial Park is a large wilderness park located in east-central British Columbia, Canada. The park protects most of the southern, and highest, regions of the Cariboo Mountains and covers 5,250 square kilometres...

. This 5400 square kilometres (2,085 sq mi) park was established in 1939 because of the volcanic field's beauty. A single road enters the park, but from it, a number of the field's volcanic features can be viewed. Short hikes lead to several volcanic features but some areas are accessible only by aircraft.

Pleistocene epoch

Based on radiocarbon
Radiocarbon dating
Radiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...

 and potassium-argon dating
Potassium-argon dating
Potassium–argon dating or K–Ar dating is a radiometric dating method used in geochronology and archeology. It is based on measurement of the product of the radioactive decay of an isotope of potassium into argon . Potassium is a common element found in many materials, such as micas, clay minerals,...

, volcanic activity in the Wells Gray-Clearwater volcanic field began in the early 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 ....

 epoch
Epoch (geology)
An epoch is a subdivision of the geologic timescale based on rock layering. In order, the higher subdivisions are periods, eras and eons. We are currently living in the Holocene epoch...

, creating valley
Valley
In geology, a valley or dale is a depression with predominant extent in one direction. A very deep river valley may be called a canyon or gorge.The terms U-shaped and V-shaped are descriptive terms of geography to characterize the form of valleys...

-filling and plateau
Plateau
In geology and earth science, a plateau , also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau...

-capping lava flows that have a total volume of approximately 25 km³ (6 cu mi). The emplacement of these lava flows spanned at least three periods of glaciation, evidence for which is preserved in the form of tuya
Tuya
A tuya is a type of distinctive, flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are somewhat rare worldwide, being confined to regions which were covered by glaciers and also had active volcanism during the same time period.-Formation:Tuyas are...

s, ice-ponded valley deposits, and subglacial mound
Subglacial mound
A subglacial mound 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 glacial ice, instead forming hyaloclastite and pillow lava...

s. The few tuyas in the region, such as Gage Hill
Gage Hill
Gage Hill is a tuya in east-central British Columbia, Canada, located in Wells Gray Provincial Park.-See also:*List of volcanoes in Canada*Volcanism of Canada*Volcanism of Western Canada...

, Hyalo Ridge
Hyalo Ridge
Hyalo Ridge is a tuya in Wells Gray Provincial Park. Hyalo Ridge last erupted during Pleistocene.-See also:* List of volcanoes in Canada* Volcanism of Canada* Volcanism of Western Canada...

, McLeod Hill
McLeod Hill
McLeod Hill is a tuya, located north of Clearwater in the Wells Gray-Clearwater volcanic field in Wells Gray Provincial Park, east-central British Columbia, Canada....

 and Mosquito Mound
Mosquito Mound
Mosquito Mound is a tuya in east-central British Columbia, Canada, located in Wells Gray Provincial Park.-See also:*List of volcanoes in Canada*Volcanism of Canada*Volcanism of Western Canada...

, were formed when magma intruded into and melted a vertical pipe in the overlying glacial ice. The partially molten mass cooled as a large block, with gravity flattening its upper surface. The glacial erosion of the tuyas suggests they erupted during the early Pleistocene epoch.

At least one explosive subaqueous volcano
Subaqueous volcano
A subaqueous volcano is a volcano formed beneath water and never builds above lake level. They are commonly in the form of gently sloping tuff cones, although they can sometimes have an unvolcano-like form, such as White Horse Bluff in the Wells Gray-Clearwater volcanic field of east-central...

 formed during the Pleistocene epoch. This subaqueous volcano, known as White Horse Bluff, is thought to have formed in three phases. Its first phase of activity was involved with water, possibly dammed by glacial ice which filled the Clearwater River
Clearwater River (British Columbia)
The Clearwater River is the largest tributary of the North Thompson River, joining it at the community of Clearwater, British Columbia. The Clearwater rises from glaciers in the Cariboo Mountains and flows in a mostly southerly direction for to the North Thompson. Its entire course, except the...

 valley. The volcano heated glacial water then flooded down the volcano's vent, creating violent steam explosions and broken lava fragments. Once the steam explosions had subsided, the broken lava fragments settled back into the glacial water, creating the unvolcano-like form of White Horse Bluff which is mostly made of fragmental volcanic glass
Volcanic glass
Volcanic glass is the amorphous product of rapidly cooling magma. Like all types of glass, it is a state of matter intermediate between the close-packed, highly ordered array of a crystal and the highly disordered array of gas...

 called hyaloclastite
Hyaloclastite
Hyaloclastite is a hydrated tuff-like breccia rich in black volcanic glass, formed during volcanic eruptions under water, under ice or where subaerial flows reach the sea or other bodies of water. It has the appearance of angular flat fragments sized between a millimeter to few centimeters...

. The volcano ceased erupting soon after breeching the surface of the glacial water.

Other volcanic events elsewhere interacted with groundwater
Groundwater
Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...

 and magma
Magma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...

 creating numerous pit crater
Pit crater
A pit crater is a depression formed by a sinking of the ground surface lying above a void or empty chamber, rather than by the eruption of a volcano or lava vent. It is often found in chains or troughs. Several craters may merge into a linear alignment...

s. Many of these pit craters have been filled with water creating several crater lake
Crater lake
A crater lake is a lake that forms in a volcanic crater or caldera, such as a maar; less commonly and with lower association to the term a lake may form in an impact crater caused by a meteorite. Sometimes lakes which form inside calderas are called caldera lakes, but often this distinction is not...

s. In some places glacial till
Till
thumb|right|Closeup of glacial till. Note that the larger grains in the till are completely surrounded by the matrix of finer material , and this characteristic, known as matrix support, is diagnostic of till....

 and fluval sands and gravels are maintained under the several lava flows that form the volcanic field. Paleosol
Paleosol
In the geosciences, paleosol can have two meanings. The first meaning, common in geology and paleontology, refers to a former soil preserved by burial underneath either sediments or volcanic deposits , which in the case of older deposits have lithified into rock...

s are found, but are rare. Glaciation has left a thick blanket of till over nearly all of the volcanic deposits and therefore outcrop is largely limited to cliffforming exposures in several valleys.

Holocene epoch

At the end of the last ice age
Ice age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...

 approximately 10,000 years ago, massive floods from the melting glacial ice carved deep canyons into the underlying plateau-capping lava flows. Most of these canyons contain river
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

s and waterfall
Waterfall
A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.-Formation:Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens...

s, such as the Murtle River
Murtle River
The Murtle River is a river in east-central British Columbia, Canada. It rises from a large unnamed glacier in the Cariboo Mountains at an elevation of and flows southwest for to the head of gigantic Murtle Lake. The river also drains Murtle Lake then flows southwest for into the Clearwater...

, Canim Falls
Canim Falls
Canim Falls is a waterfall on the Canim River between Canim and Mahood Lakes in the Cariboo region of the Central Interior of British Columbia, Canada. It is approximately in height as measured in 1968 , and is cut into a lava plateau associated with the Wells Gray-Clearwater volcanic field which...

, Spahats Falls
Spahats Falls
Spahats Creek Falls, also called Spahats Falls, is a waterfall on Spahats Creek within Wells Gray Provincial Park of British Columbia, Canada. Common references place the falls at around tall, but taking into account the second tier, it is closer to 75–80 meters tall...

 and the 142 metres (465.9 ft) high Helmcken Falls
Helmcken Falls
Helmcken Falls is a waterfall on the Murtle River within Wells Gray Provincial Park in British Columbia, Canada. The protection of Helmcken Falls was one of the reasons for the creation of Wells Gray Provincial Park in 1939....

. The faces of the basaltic lava flows and waterfalls remain vertical due to the nature of the basaltic lava flows. Basaltic lava shrinks as it cools and forms vertical columns of rock called columnar basalt. More recently, the southern end of the volcanic field has experienced continuous volcanic activity since the end of the last ice age. This volcanic activity occurred in three areas; Spanish Creek, Ray Lake
Ray Lake
Ray Lake is a lake located in Wells Gray Provincial Park, east-central British Columbia, Canada. It is fed by and drained by Falls Creek which flows into the Clearwater River at its outlet from Clearwater Lake.-Naming:...

 and Kostal Lake
Kostal Lake
Kostal Lake is a lake located in Wells Gray Provincial Park, east-central British Columbia, Canada. It is located west of Murtle Lake and east of Clearwater Lake.-Naming:...

 which were followed by lava fountain
Lava fountain
A lava fountain is a volcanic phenomenon in which lava is forcefully but non-explosively ejected from a crater, vent, or fissure. Lava fountains may reach heights of up to . They may occur as a series of short pulses, or a continuous jet of lava. They are commonly seen in Hawaiian eruptions.-See...

 eruptions creating cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

s and lava flows.

Volcanism in the Spanish Creek and Ray Lake areas were synglacial but continued after the glacial ice had melted away. Two cinder cones, known as Flourmill Cone
Flourmill Cone
The Flourmill Volcanoes, also known as The Flourmills, are a small volcano range near the west boundary of Wells Gray Provincial Park in east-central British Columbia, Canada...

 and Pointed Stick Cone
Pointed Stick Cone
Pointed Stick Cone is a cinder cone in east-central British Columbia, Canada, located in Wells Gray Provincial Park.-See also:* List of volcanoes in Canada* Volcanism of Canada* Volcanism of Western Canada...

, were created in the Spanish Creek area. Lava flows from the two cinder cones lie on glaciated bedrock without an intervening paleosol
Paleosol
In the geosciences, paleosol can have two meanings. The first meaning, common in geology and paleontology, refers to a former soil preserved by burial underneath either sediments or volcanic deposits , which in the case of older deposits have lithified into rock...

, indicating an early Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

 age.

Eruptions near Ray Lake built a cinder cone known as Dragon Cone
Dragon Cone
Dragon Cone is a monogenetic cinder cone located in Wells Gray Provincial Park in east-central British Columbia. It is the source of a long lava flow, called Dragon's Tongue. This lava covered the floor of narrow Falls Creek Valley and terminated at the Clearwater River, damming it to a height of ...

 and concluded with an approximately 16 kilometres (9.9 mi) long aā lava flow that has been radiocarbon dated
Radiocarbon dating
Radiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...

 at about 7,600 years old. This lava flow, known as "Dragon's Tongue", is at least 15 kilometres (9.3 mi) thick at the proximal end, but thins to 3 metres (9.8 ft) at the distal end, damming the southern end of Clearwater Lake
Clearwater Lake
-Lakes:Canada*Clearwater Lake *Clearwater Lakes, the English name of the Lac à l'Eau Claire, a pair of impact craters in northern QuébecUnited States*Clearwater Lake , a lake and campsite in the Ocala National Forest, Florida...

. Tree molds are maintained within the lava flow at the lower end.

The latest volcanic eruption created a small tree-covered basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic cinder cone at the east end of Kostal Lake called Kostal Cone
Kostal Cone
Kostal Cone, also called Kostal Volcano, is a young cinder cone in Wells Gray Provincial Park in east-central British Columbia, Canada. It rises from the northeast shore of Kostal Lake in the Cariboo Mountains...

 perhaps as recently as 400 years ago, making it one of the youngest volcanoes in Canada based on tree-growth data.

Origins

The Wells Gray-Clearwater volcanic field began forming approximately 3,500,000 years ago and has grown steadily since then. The tectonic causes of the volcanism that have produced the Wells Gray-Clearwater volcanic field are not yet clear and are therefore a matter of ongoing research. It is approximately 250 kilometres (155.3 mi) inland from the north-south trending 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...

 and is along-strike from the Nootka Fault
Nootka Fault
The Nootka Fault is an active transform fault running southwest from Nootka Island, near Vancouver Island, British Columbia, Canada.-Geology:...

 on the British Columbia 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....

, which has been subducting
Subduction
In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate, sinking into the Earth's mantle, as the plates converge. These 3D regions of mantle downwellings are known as "Subduction Zones"...

 under the North American Plate
North American Plate
The North American Plate is a tectonic plate covering most of North America, Greenland, Cuba, Bahamas, and parts of Siberia, Japan and Iceland. It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust...

 at the Cascadia subduction zone
Cascadia subduction zone
The Cascadia subduction zone is a subduction zone, a type of convergent plate boundary that stretches from northern Vancouver Island to northern California. It is a very long sloping fault that separates the Juan de Fuca and North America plates.New ocean floor is being created offshore of...

. The Wells Gray volcanics are mostly alkali
Alkali
In chemistry, an alkali is a basic, ionic salt of an alkali metal or alkaline earth metal element. Some authors also define an alkali as a base that dissolves in water. A solution of a soluble base has a pH greater than 7. The adjective alkaline is commonly used in English as a synonym for base,...

 olivine
Olivine
The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....

 basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

, with some lava flows comprising mantle
Mantle (geology)
The mantle is a part of a terrestrial planet or other rocky body large enough to have differentiation by density. The interior of the Earth, similar to the other terrestrial planets, is chemically divided into layers. The mantle is a highly viscous layer between the crust and the outer core....

 xenolith
Xenolith
A xenolith is a rock fragment which becomes enveloped in a larger rock during the latter's development and hardening. In geology, the term xenolith is almost exclusively used to describe inclusions in igneous rock during magma emplacement and eruption...

s. Basalts of the Wells Gray-Clearwater volcanic field have been considered to be the easternmost expression of the Anahim Volcanic Belt
Anahim Volcanic Belt
The Anahim Volcanic Belt is a long volcanic belt, stretching from just north of Vancouver Island to near Quesnel, British Columbia, Canada. The Anahim Volcanic Belt has had three main magmatic episodes: 15–13 Ma, 9–6 Ma, and 3–1 Ma. The volcanoes generally become younger eastward at a rate of to ...

. However, its relationship is unknown because the age-location trend does not reach into the Wells Gray-Clearwater area, and the Wells Gray-Clearwater volcanic field is not along trend with the Anahim Volcanic Belt. The Wells Gray volcanics were thought to have formed by crustal
Crust (geology)
In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle...

 thinning and the existence of crustal penetrating structures.

More recent studies by volcanologists
Volcanology
Volcanology is the study of volcanoes, lava, magma, and related geological, geophysical and geochemical phenomena. The term volcanology is derived from the Latin word vulcan. Vulcan was the ancient Roman god of fire....

 associated with the Geological Survey of Canada have indicated that the subducted extension of the Nookta Fault may be the primary cause of the alkalic structure of the Wells Gray-Clearwater volcanic field. The volcanism might have been mostly generated by asthenospheric
Asthenosphere
The asthenosphere is the highly viscous, mechanically weak and ductilely-deforming region of the upper mantle of the Earth...

 upwelling possibly by displacement along the transform fault
Transform fault
A transform fault or transform boundary, also known as conservative plate boundary since these faults neither create nor destroy lithosphere, is a type of fault whose relative motion is predominantly horizontal in either sinistral or dextral direction. Furthermore, transform faults end abruptly...

. If the transform fault had a section of vertical tearing to contain potentially different dip angles between the Explorer
Explorer Plate
The Explorer Plate is an oceanic tectonic plate beneath the Pacific Ocean off the west coast of Vancouver Island, Canada.The eastern boundary of the Explorer Plate is being slowly subducted under the North American Plate, to which it may eventually accrete owing to the slow rate of subduction...

 and Juan de Fuca Plate
Juan de Fuca Plate
The Juan de Fuca Plate, named after the explorer of the same name, is a tectonic plate, generated from the Juan de Fuca Ridge, and subducting under the northerly portion of the western side of the North American Plate at the Cascadia subduction zone...

s, the subducted plate asthenosphere may possibly flow upward into the mantle wedge. Similarly, if the displacement had a section of extension, a horizontal slab window
Slab window
In geology, a slab window is a gap that forms in a subducted oceanic plate when a mid-ocean ridge meets with a subduction zone. They are commonly associated with the formation of convergent plate boundaries and they have had significant effects on the formation of the North American Cordillera.A...

-like gap would have developed, again allowing a pathway for upwelling magma. In either case, the unsettled asthenosphere might have experienced low degrees of decompressional melting and interacted with North American lithosphere
Lithosphere
The lithosphere is the rigid outermost shell of a rocky planet. On Earth, it comprises the crust and the portion of the upper mantle that behaves elastically on time scales of thousands of years or greater.- Earth's lithosphere :...

 to yield within plate compositions.

Lava composition

The composition of some lava flows in the Wells Gray-Clearwater volcanic field are unusual because they include small, angular to rounded fragments of rock called nodule
Nodule (geology)
A nodule in petrology or mineralogy is a secondary structure, generally spherical or irregularly rounded in shape. Nodules are typically solid replacement bodies of chert or iron oxides formed during diagenesis of a sedimentary rock...

s and crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

s that come from the mantle
Mantle (geology)
The mantle is a part of a terrestrial planet or other rocky body large enough to have differentiation by density. The interior of the Earth, similar to the other terrestrial planets, is chemically divided into layers. The mantle is a highly viscous layer between the crust and the outer core....

. These green nodules are known as peridotite
Peridotite
A peridotite is a dense, coarse-grained igneous rock, consisting mostly of the minerals olivine and pyroxene. Peridotite is ultramafic, as the rock contains less than 45% silica. It is high in magnesium, reflecting the high proportions of magnesium-rich olivine, with appreciable iron...

s because they are mostly made of a magnesium
Magnesium
Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...

 iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 silicate
Silicate
A silicate is a compound containing a silicon bearing anion. The great majority of silicates are oxides, but hexafluorosilicate and other anions are also included. This article focuses mainly on the Si-O anions. Silicates comprise the majority of the earth's crust, as well as the other...

 mineral called olivine
Olivine
The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....

. These lava flows also comprise large crystals of olivine, plagioclase
Plagioclase
Plagioclase is an important series of tectosilicate minerals within the feldspar family. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a solid solution series, more properly known as the plagioclase feldspar series...

, and pyroxene
Pyroxene
The pyroxenes are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. They share a common structure consisting of single chains of silica tetrahedra and they crystallize in the monoclinic and orthorhombic systems...

 that crystallized deep within the Earth's crust
Crust (geology)
In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle...

 and mantle. The lavas and nodules they contain are similar to those erupted at Volcano Mountain
Volcano Mountain
Volcano Mountain is an active cinder cone in central Yukon Territory, Canada, located a short distance north of Fort Selkirk, near the confluence of the Pelly and Yukon Rivers...

 in the Yukon
Yukon
Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....

. The nodules help volcanologists
Volcanology
Volcanology is the study of volcanoes, lava, magma, and related geological, geophysical and geochemical phenomena. The term volcanology is derived from the Latin word vulcan. Vulcan was the ancient Roman god of fire....

 and other geoscientists to verify what the mantle beneath the volcanic field is like.

Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

 lava flows are more alkalic than the 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 ....

 lava flows and comprise several xenolith
Xenolith
A xenolith is a rock fragment which becomes enveloped in a larger rock during the latter's development and hardening. In geology, the term xenolith is almost exclusively used to describe inclusions in igneous rock during magma emplacement and eruption...

s of chromium
Chromium
Chromium is a chemical element which has the symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point. It is also odorless, tasteless, and malleable...

-spinel
Spinel
Spinel is the magnesium aluminium member of the larger spinel group of minerals. It has the formula MgAl2O4. Balas ruby is an old name for a rose-tinted variety.-Spinel group:...

 lherzolite
Lherzolite
Lherzolite is a type of ultramafic igneous rock. It is a coarse grained rock consisting of 40 to 90% olivine along with significant orthopyroxene and lesser calcic chromium rich clinopyroxene. Minor minerals include chromium and aluminium spinels and garnets. Plagioclase can occur in lherzolites...

, spinel clinopyroxenite, and rare ferroan
Ferrite
Ferrite may refer to:* Ferrite , iron or iron alloys with a body centred cubic crystal structure.* Ferrite , ferrimagnetic ceramic materials used in magnetic applications....

 websterite and spinel wehrlite. Xenoliths do not exist in the older lava flows. However, chemical evidence indicates that every lava flow was produced in a similar way by low degrees of piecemeal melting. The melts originally came from the upper mantle which, over time, was progressively depleted by every following melting event.

Current activity

The Wells Gray-Clearwater volcanic field is one of the 10 volcanic areas in Canada associated with recent seismic activity
Seismology
Seismology is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. The field also includes studies of earthquake effects, such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, oceanic,...

; the others are Castle Rock
Castle Rock (volcano)
Castle Rock is a volcanic neck located west of Iskut and 8 km northwest of Tuktsayda Mountain in British Columbia, Canada. It is part of the Pacific Ring of Fire that includes over 160 active volcanoes and is in the Klastline Group, Northern Cordilleran Volcanic Province and last erupted in...

, Mount Edziza
Mount Edziza
Mount Edziza is a stratovolcano in the Stikine Country of northwestern British Columbia, Canada. The volcano and the surrounding area are protected within Mount Edziza Provincial Park. It consists of a complex of multiple peaks and ridges, with several glaciers flowing in all directions. The summit...

, Mount Cayley
Mount Cayley
Mount Cayley is a potentially active stratovolcano in Squamish-Lillooet Regional District of southwestern British Columbia, Canada. Located north of Squamish and west of Whistler in the Pacific Ranges of the Coast Mountains, it rises above the Squamish River to the west and above the Cheakamus...

, Hoodoo Mountain
Hoodoo Mountain
Hoodoo Mountain is a potentially active flat-topped stratovolcano in the Stikine Country of northwestern British Columbia, Canada, located northeast of Wrangell, Alaska on the north side of the lower Iskut River and east of its junction with the Stikine River...

, The Volcano
The Volcano (British Columbia)
The Volcano, also known as Lava Fork volcano, is a small cinder cone in the Boundary Ranges of the Coast Mountains in northwestern British Columbia, Canada. It is located approximately northwest of the small community of Stewart near the head of Lava Fork...

, Crow Lagoon
Crow Lagoon
Crow Lagoon is a little-known volcanic center located north of Prince Rupert, British Columbia, Canada. There are beds of thick, basaltic tephra that are of Holocene age....

, Mount Meager
Mount Meager
Mount Meager, originally known as Meager Mountain, is a complex volcano in the Sea-to-Sky Corridor of southwestern British Columbia, Canada. It is located north of Vancouver at the northern end of the Pemberton Valley. Part of the Cascade Volcanic Arc of western North America, its summit is above...

, Mount Garibaldi
Mount Garibaldi
Mount Garibaldi is a potentially active stratovolcano in the Sea to Sky Country of British Columbia, north of Vancouver, Canada. Located in the southernmost Coast Mountains, it is one of the most recognized peaks in the South Coast region, as well as British Columbia's best known volcano...

 and Nazko Cone
Nazko Cone
Nazko Cone is a small potentially active basaltic cinder cone in central British Columbia, Canada, located 75 km west of Quesnel and 150 kilometers southwest of Prince George. It is considered the easternmost volcano in the Anahim Volcanic Belt. The small tree-covered cone rises 120 m above...

. Seismic data suggests that these volcanoes still contain living magma
Magma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...

 plumbing systems, indicating possible future eruptive activity. Although the available data does not allow a clear conclusion, these observations are further indications that some of Canada's volcanoes are potentially active, and that their associated hazards may be significant. Beneath areas of monogenetic cinder cone activity, such as the Wells Gray-Clearwater volcanic field, the seismicity appears to be more dispersed. In a few cases earthquakes are clustered in time and space, suggestive of volcanic earthquake swarms.

Volcanic hazards

Lava eruptions

Because the Wells Gray-Clearwater volcanic field is in a remote location, danger from lava eruptions would be low to moderate. Magma with low levels of silica (as in basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

) commonly extend tens of kilometers from the volcano's vent. The leading edges of basalt flows can travel as fast as 10 kilometres per hour (6.2 mph) on steep slopes but they typically advance less than 1 kilometre per hour (0.621371192734431 mph) on gentle slopes. But when basalt lava flows are confined within a channel or lava tube
Lava tube
Lava tubes are natural conduits through which lava travels beneath the surface of a lava flow, expelled by a volcano during an eruption. They can be actively draining lava from a source, or can be extinct, meaning the lava flow has ceased and the rock has cooled and left a long, cave-like...

 on a steep slope, the main body of the flow can reach velocities more than 30 kilometres per hour (18.6 mph). Based on past volcanic activity, the Wells Gray-Clearwater volcanic field has a long history of producing quiet lava fountain
Lava fountain
A lava fountain is a volcanic phenomenon in which lava is forcefully but non-explosively ejected from a crater, vent, or fissure. Lava fountains may reach heights of up to . They may occur as a series of short pulses, or a continuous jet of lava. They are commonly seen in Hawaiian eruptions.-See...

ing-style eruptions. Such eruptions consist of ejection of incandescent cinder
Cinder
A cinder is a pyroclastic material. Cinders are extrusive igneous rocks. Cinders are similar to pumice, which has so many cavities and is such low-density that it can float on water...

, lapilli
Lapilli
Lapilli is a size classification term for tephra, which is material that falls out of the air during a volcanic eruption or during some meteorite impacts. Lapilli means "little stones" in Latin. They are in some senses similar to ooids or pisoids in calcareous sediments.By definition lapilli range...

 and lava bomb
Volcanic bomb
A volcanic bomb is a mass of molten rock larger than 65 mm in diameter, formed when a volcano ejects viscous fragments of lava during an eruption. They cool into solid fragments before they reach the ground. Because volcanic bombs cool after they leave the volcano, they do not have grains...

s to altitudes of tens to hundreds of metres. They are small to medium in volume, with sporadic violence. Since the region is mostly forested and lava flows are likely to travel long distances, it is possible lava eruptions could start large forest fires and some river valleys might be dammed.

Explosive eruptions

More violent eruptions are possible only in unique circumstances, such as an eruption into a lake. Any future eruption is most likely to affect only a limited area downslope from the volcano. Poisonous substances, such as volcanic gas
Volcanic gas
|250px|thumb|right|Image of the [[rhyolitic]] [[lava dome]] of [[Chaitén Volcano]] during its 2008-2010 eruption.Volcanic gases include a variety of substances given off by active volcanoes...

, includes a variety of substances. These include gases trapped in cavities (vesicles
Vesicular texture
Vesicular texture is a volcanic rock texture characterised by a rock being pitted with many cavities at its surface and inside. The texture is often found in extrusive aphanitic, or glassy, igneous rock...

) in volcanic rock
Volcanic rock
Volcanic rock is a rock formed from magma erupted from a volcano. In other words, it is an igneous rock of volcanic origin...

s, dissolved or dissoclated gas
Gas
Gas is one of the three classical states of matter . Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point , boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons...

es in magma
Magma
Magma is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and dissolved gas and sometimes also gas bubbles. Magma often collects in...

 and lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

, or gases emanating directly from lava or indirectly through ground water heated by volcanic action
Hydrothermal circulation
Hydrothermal circulation in its most general sense is the circulation of hot water; 'hydros' in the Greek meaning water and 'thermos' meaning heat. Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust...

. The volcanic gases that pose the greatest potential hazard to people, animals, agriculture, and property are sulfur dioxide
Sulfur dioxide
Sulfur dioxide is the chemical compound with the formula . It is released by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide unless the sulfur compounds are removed before burning the fuel...

, carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...

 and hydrogen fluoride
Hydrogen fluoride
Hydrogen fluoride is a chemical compound with the formula HF. This colorless gas is the principal industrial source of fluorine, often in the aqueous form as hydrofluoric acid, and thus is the precursor to many important compounds including pharmaceuticals and polymers . HF is widely used in the...

. Locally, sulfur dioxide gas can lead to acid rain
Acid rain
Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it possesses elevated levels of hydrogen ions . It can have harmful effects on plants, aquatic animals, and infrastructure. Acid rain is caused by emissions of carbon dioxide, sulfur dioxide and nitrogen...

 and air pollution downwind from the volcano.

Monitoring

Currently the Wells Gray-Clearwater volcanic field is not monitored closely enough by the Geological Survey of Canada to ascertain how active the volcanic field's magma system is. The existing network of seismograph
Seismometer
Seismometers are instruments that measure motions of the ground, including those of seismic waves generated by earthquakes, volcanic eruptions, and other seismic sources...

s has been established to monitor tectonic earthquakes and is too far away to provide a good indication of what is happening beneath the volcanic field. It may sense an increase in activity if the volcanic field becomes very restless, but this may only provide a warning for a large eruption. It might detect activity only after the volcanic field has started erupting.

A possible way to detect an eruption is studying the volcanic field's geological history since every volcano has its own pattern of behaviour, in terms of its eruption style, magnitude and frequency, so that its future eruption is expected to be similar to its previous eruptions. But this would likely be abandoned in part because of the volcanic field's remoteness.

While there is a likelihood of Canada being critically affected by local or close by volcanic eruptions argues that some kind of improvement program is required. Benefit-cost thoughts are critical to dealing with natural hazards. However, a benefit-cost examination needs correct data about the hazard types, magnitudes and occurrences. These do not exist for volcanoes in British Columbia or elsewhere in Canada in the detail required.

Other volcanic techniques, such as hazard mapping, displays a volcano's eruptive history in detail and speculates an understanding of the hazardous activity that could possibly be expected in the future. At present no hazard maps have been created for the Wells Gray-Clearwater volcanic field because the level of knowledge is insufficient due to its remoteness. A large volcanic hazard program has never existed within the Geological Survey of Canada. The majority of information has been collected in a lengthy, separate way from the support of several employees, such as volcanologist
Volcanologist
A volcanologist is a person who studies the formation of volcanoes, and their current and historic eruptions. Volcanologists frequently visit volcanoes, especially active ones, to observe volcanic eruptions, collect eruptive products including tephra , rock and lava samples...

s and other geologic scientist
Scientist
A scientist in a broad sense is one engaging in a systematic activity to acquire knowledge. In a more restricted sense, a scientist is an individual who uses the scientific method. The person may be an expert in one or more areas of science. This article focuses on the more restricted use of the word...

s. Current knowledge is best established at Mount Meager
Mount Meager
Mount Meager, originally known as Meager Mountain, is a complex volcano in the Sea-to-Sky Corridor of southwestern British Columbia, Canada. It is located north of Vancouver at the northern end of the Pemberton Valley. Part of the Cascade Volcanic Arc of western North America, its summit is above...

 and is likely to rise considerably with a temporary mapping and monitoring project. Knowledge at the Wells Gray-Clearwater volcanic field and other volcanic areas in British Columbia is not as established, but certain contributions are being done at least Mount Cayley
Mount Cayley
Mount Cayley is a potentially active stratovolcano in Squamish-Lillooet Regional District of southwestern British Columbia, Canada. Located north of Squamish and west of Whistler in the Pacific Ranges of the Coast Mountains, it rises above the Squamish River to the west and above the Cheakamus...

. An intensive program classifiying infrastructural exposure near all young Canadian volcanoes and quick hazard assessments at each individual volcanic edifice associated with recent seismic activity would be in advance and would produce a quick and productive determination of priority areas for further efforts.

The existing network of seismographs to monitor tectonic earthquakes has existed since 1975, although it remained small in population until 1985. Apart from a few short-term seismic monitoring experiments by the Geological Survey of Canada, no volcano monitoring has been accomplished at the Wells Gray-Clearwater volcanic field or at other volcanoes in Canada at a level approaching that in other established countries with historically active volcanoes. Active or restless volcanoes are usually monitored using at least three seismographs all within approximately 15 kilometres (9.3 mi), and frequently within 5 kilometres (3.1 mi), for better sensitivity of detection and reduced location errors, particularly for earthquake depth. Such monitoring detects the risk of an eruption, offering a forecasting capability which is important to mitigating volcanic risk. Currently the Wells Gray-Clearwater volcanic field does not have a seismograph closer than 59 kilometres (36.7 mi). With increasing distance and declining numbers of seismographs used to indicate seismic activity, the prediction capability is reduced because earthquake location accuracy and depth decreases, and the network becomes not as accurate. However, at least one possible volcanic earthquake swarm
Earthquake swarm
Earthquake swarms are events where a local area experiences sequences of many earthquakes striking in a relatively short period of time. The length of time used to define the swarm itself varies, but the United States Geological Survey points out that an event may be on the order of days, weeks, or...

 has been noticed east of the Wells Gray-Clearwater volcanic field. The inaccurate earthquake locations in the Wells Gray-Clearwater volcanic field are a few kilometers, and in more isolated northern regions they are up to 10 kilometres (6.2 mi). The location magnitude level in the Wells Gray-Clearwater volcanic field is about magnitude 1 to 1.5, and elsewhere it is magnitude 1.5 to 2. At carefully monitored volcanoes both the located and noticed events are recorded and surveyed immediately to improve the understanding of a future eruption. Undetected events are not recorded or surveyed in British Columbia immediately, nor in an easy-to-access process.

In countries like Canada it is possible that small precursor earthquake swarms might go undetected, particularly if no events were observed; more significant events in larger swarms would be detected but only a minor subdivision of the swarm events would be complex to clarify them with confidence as volcanic in nature, or even associate them with an individual volcanic edifice.

Notable vents

Name Height Coordinates Type Age of last eruption
metres feet
Quesnel Lake
Quesnel Lake
Quesnel Lake is a glacial lake or fjord in British Columbia, Canada, and is the origin of the Quesnel River. With a maximum depth of 610 meters , it is the deepest lake in British Columbia, though not the deepest lake in Canada, as is often claimed. That distinction belongs to Great Slave Lake...

12924,238.8 52.65°N 120.98°W Cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 
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 ....

Kostal Cone
Kostal Cone
Kostal Cone, also called Kostal Volcano, is a young cinder cone in Wells Gray Provincial Park in east-central British Columbia, Canada. It rises from the northeast shore of Kostal Lake in the Cariboo Mountains...

14404,724.4 52.17°N 119.94°W Cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 
Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

Pillow Creek
Pillow Creek
Pillow Creek is a creek in east-central British Columbia, Canada, located in the northeast corner of Wells Gray Provincial Park.Pillow Creek is home to a subglacial volcano that formed and last erupted during the Pleistocene period.-See also:...

18296,000.7 52.02°N 119.84°W Subglacial volcano
Subglacial volcano
A subglacial volcano, also known as a glaciovolcano, is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava...

 
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 ....

Gage Hill
Gage Hill
Gage Hill is a tuya in east-central British Columbia, Canada, located in Wells Gray Provincial Park.-See also:*List of volcanoes in Canada*Volcanism of Canada*Volcanism of Western Canada...

10903,576.1 52.05°N 120.01°W Tuya
Tuya
A tuya is a type of distinctive, flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are somewhat rare worldwide, being confined to regions which were covered by glaciers and also had active volcanism during the same time period.-Formation:Tuyas are...

 
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 ....

Dragon Cone
Dragon Cone
Dragon Cone is a monogenetic cinder cone located in Wells Gray Provincial Park in east-central British Columbia. It is the source of a long lava flow, called Dragon's Tongue. This lava covered the floor of narrow Falls Creek Valley and terminated at the Clearwater River, damming it to a height of ...

18506,069.6 52.25°N 120.02°W Cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 
Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

Flourmill Cone
Flourmill Cone
The Flourmill Volcanoes, also known as The Flourmills, are a small volcano range near the west boundary of Wells Gray Provincial Park in east-central British Columbia, Canada...

14954,904.9 52.05°N 120.32°W Cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 
Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

Pointed Stick Cone
Pointed Stick Cone
Pointed Stick Cone is a cinder cone in east-central British Columbia, Canada, located in Wells Gray Provincial Park.-See also:* List of volcanoes in Canada* Volcanism of Canada* Volcanism of Western Canada...

18205,971.1 52.24°N 120.08°W Cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 
Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

Spanish Lake Centre 17705,807.1 52.07°N 120.31°W Cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 
Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

Spanish Bonk
Spanish Bonk
Spanish Bonk is a volcanic plug located in the Quesnel Highland of the Wells Gray-Clearwater volcanic field in southeastern British Columbia, Canada. Spanish Bonk last erupted during the Pleistocene.-External links:*...

17705,807.1 52.13°N 120.37°W Volcanic neck
Volcanic plug
A volcanic plug, also called a volcanic neck or lava neck, is a volcanic landform created when magma hardens within a vent on an active volcano. When forming, a plug can cause an extreme build-up of pressure if volatile-charged magma is trapped beneath it, and this can sometimes lead to an...

 
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 ....

Ray Mountain
Ray Mountain
Ray Mountain is a subglacial mound in Wells Gray Provincial Park, British Columbia, Canada. Ray Mountain last erupted during the Pleistocene. It is part of the Wells Gray-Clearwater volcanic field....

20506,725.7 52.24°N 120.11°W Subglacial mound
Subglacial mound
A subglacial mound 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 glacial ice, instead forming hyaloclastite and pillow lava...

 
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 ....

Spanish Mump
Spanish Mump
Spanish Mump is a subglacial mound in east-central British Columbia, Canada, located in the northeastern corner of Wells Gray Provincial Park.-See also:* List of volcanoes in Canada* Volcanism of Canada* Volcanism of Western Canada...

18005,905.5 52.16°N 120.33°W Subglacial mound
Subglacial mound
A subglacial mound 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 glacial ice, instead forming hyaloclastite and pillow lava...

 
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 ....

Jack's Jump
Jack's Jump
Jack's Jump is a subglacial volcano in east-central British Columbia, Canada, located at the northeastern end of Wells Gray Provincial Park.-See also:* List of volcanoes in Canada* Volcanism of Canada* Volcanism of Western Canada...

18956,217.2 52.12°N 120.05°W Subglacial volcano
Subglacial volcano
A subglacial volcano, also known as a glaciovolcano, is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava...

 
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 ....

Hyalo Ridge
Hyalo Ridge
Hyalo Ridge is a tuya in Wells Gray Provincial Park. Hyalo Ridge last erupted during Pleistocene.-See also:* List of volcanoes in Canada* Volcanism of Canada* Volcanism of Western Canada...

20126,601 52.11°N 120.36°W Tuya
Tuya
A tuya is a type of distinctive, flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are somewhat rare worldwide, being confined to regions which were covered by glaciers and also had active volcanism during the same time period.-Formation:Tuyas are...

 
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 ....

McLeod Hill
McLeod Hill
McLeod Hill is a tuya, located north of Clearwater in the Wells Gray-Clearwater volcanic field in Wells Gray Provincial Park, east-central British Columbia, Canada....

12504,101 52.02°N 120.01°W Tuya
Tuya
A tuya is a type of distinctive, flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are somewhat rare worldwide, being confined to regions which were covered by glaciers and also had active volcanism during the same time period.-Formation:Tuyas are...

 
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 ....

Mosquito Mound
Mosquito Mound
Mosquito Mound is a tuya in east-central British Columbia, Canada, located in Wells Gray Provincial Park.-See also:*List of volcanoes in Canada*Volcanism of Canada*Volcanism of Western Canada...

10653,494.1 52.02°N 120.18°W Tuya
Tuya
A tuya is a type of distinctive, flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are somewhat rare worldwide, being confined to regions which were covered by glaciers and also had active volcanism during the same time period.-Formation:Tuyas are...

 
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 ....

Buck Hill
Buck Hill (British Columbia)
Buck Hill is a hill in east-central British Columbia, Canada, located north of Clearwater. It rises from the west slope of Trophy Mountain. Buck Hill is just outside the boundary of Wells Gray Provincial Park.-Geology:...

15855,200.1 51.08°N 119.98°W Cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 
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 ....

Ida Ridge
Ida Ridge
Ida Ridge is an eroded cinder cone in east-central British Columbia, Canada, located in the southeastern corner of Wells Gray Provincial Park.-See also:* List of volcanoes in Canada* Volcanism of Canada* Volcanism of Western Canada...

19816,499.3 51.08°N 119.94°W Cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 
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 ....

Fiftytwo Ridge
Fiftytwo Ridge
Fiftytwo Ridge is a mountain ridge in east-central British Columbia, Canada, located just southwest of Battle Mountain at the southeastern end of Wells Gray Provincial Park.-Geology:...

20156,610.9 51.93°N 119.89°W Subglacial volcano
Subglacial volcano
A subglacial volcano, also known as a glaciovolcano, is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava...

 
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 ....

Flatiron
Flatiron (volcano)
The Flatiron is the name for an eroded volcanic outcrop in east-central British Columbia, Canada, located in Wells Gray Provincial Park.The Flatiron is high, long and generally about wide...

7302,395 51.88°N 120.05°W Volcanic outcrop
Outcrop
An outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth. -Features:Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial deposits are covered by a mantle of soil and vegetation and cannot be...

 
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 ....

White Horse Bluff 7752,542.7 51.09°N 120.11°W Subaqueous volcano
Subaqueous volcano
A subaqueous volcano is a volcano formed beneath water and never builds above lake level. They are commonly in the form of gently sloping tuff cones, although they can sometimes have an unvolcano-like form, such as White Horse Bluff in the Wells Gray-Clearwater volcanic field of east-central...

 
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 ....

Pyramid Mountain
Pyramid Mountain (volcano)
Pyramid Mountain is a subglacial mound located on the Murtle Plateau in Wells Gray Provincial Park, east-central British Columbia, Canada.-Formation:...

10953,592.5 51.99°N 120.01°W Subglacial volcano
Subglacial volcano
A subglacial volcano, also known as a glaciovolcano, is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava...

 
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 ....


See also

  • Volcanism of Canada
  • Volcanism of Western Canada
    Volcanism of Western Canada
    Volcanism of Western Canada produces lava flows, lava plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, submarine volcanoes, calderas, diatremes and maars, along with examples of more less common volcanic forms such as tuyas and subglacial mounds.-Volcanic belts:*Anahim...

  • Chilcotin Group
  • Anahim Volcanic Belt
    Anahim Volcanic Belt
    The Anahim Volcanic Belt is a long volcanic belt, stretching from just north of Vancouver Island to near Quesnel, British Columbia, Canada. The Anahim Volcanic Belt has had three main magmatic episodes: 15–13 Ma, 9–6 Ma, and 3–1 Ma. The volcanoes generally become younger eastward at a rate of to ...

  • 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...

  • Northern Cordilleran Volcanic Province
    Northern Cordilleran volcanic province
    The Northern Cordilleran Volcanic Province , formerly known as the Stikine Volcanic Belt, is a geologic province defined by the occurrence of Miocene to Holocene volcanoes in the Pacific Northwest of North America...

  • List of volcanoes in Canada
  • Geology of the Pacific Northwest
    Geology of the Pacific Northwest
    The geology of the Pacific Northwest refers to the study of the composition , structure, physical properties and the processes that shape the Pacific Northwest region of the United States and Canada...

  • Maar
    Maar
    A maar is a broad, low-relief volcanic crater that is caused by a phreatomagmatic eruption, an explosion caused by groundwater coming into contact with hot lava or magma. A maar characteristically fills with water to form a relatively shallow crater lake. The name comes from the local Moselle...

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK