Mount Edziza ( ; ) is a

volcanic A volcano is commonly defined as a vent or fissure 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 fo ...

mountain in

Cassiar Land District Cassiar Land District is a cadastral survey subdivision of the province of British Columbia, Canada, created with rest of those on Mainland British Columbia via the Lands Act of the Colony of British Columbia (1858–1866), Colony of British Columb ...

of northwestern

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

, Canada. It is located on the

Big Raven Plateau The Big Raven Plateau is an intermontane plateau in Cassiar Land District of northwestern British Columbia, Canada. It lies on the Tahltan Highland and is surrounded by several valleys, including those of Mess Creek, Kakiddi Creek, Chakima Creek ...

of the

Tahltan Highland The Tahltan Highland is an upland area of plateau and relatively lower mountain ranges in British Columbia, Canada, lying east of the Boundary Ranges and south of the Inklin River (the east fork of the Taku River). Its eastern boundary is formed ...

which extends along the western side of the

Stikine Plateau The Stikine Plateau is a plateau in northern British Columbia, Canada. It lies between the Boundary Ranges of the Coast Mountains on the west and southwest and the Cassiar Mountains along its northeast, and between the Skeena Mountains on its so ...

. Mount Edziza has an elevation of , making it the highest point of the

Mount Edziza volcanic complex The Mount Edziza volcanic complex ( ; abbreviated MEVC) is a group of volcanoes and associated lava flows in northwestern British Columbia, Canada. Located on the Tahltan Highland, it is southeast of Telegraph Creek and southwest of Dease Lak ...

and one of the highest

volcano A volcano is commonly defined as a vent or fissure 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 oft ...

es in Canada. However, it had an elevation of at least before its formerly cone-shaped summit was likely destroyed by a violent eruption in the geologic past; its current flat summit contains an ice-filled,

crater A crater is a landform consisting of a hole or depression (geology), depression on a planetary surface, usually caused either by an object hitting the surface, or by geological activity on the planet. A crater has classically been described ...

. The mountain contains several

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 ...

cinder cone A cinder cone or scoria cone is a steep, volcanic cone, conical landform of loose pyroclastic rock, pyroclastic fragments, such as volcanic ash, clinkers, or scoria that has been built around a volcanic vent. The pyroclastic fragments are forme ...

s and

lava field A lava field, sometimes called a lava bed, is a large, mostly flat area of lava flows. Such features are generally composed of highly fluid basalt lava, and can extend for tens or hundreds of kilometers across the underlying terrain. Morp ...

s on its flanks, as well as an

ice cap In glaciology, an ice cap is a mass of ice that covers less than of land area (usually covering a highland area). Larger ice masses covering more than are termed ice sheets. Description By definition, ice caps are not constrained by topogra ...

containing several outlet glaciers which extend to lower elevations. All sides of Mount Edziza are drained by

tributaries A tributary, or an ''affluent'', is a stream or river that flows into a larger stream ('' main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which the ...

of Mess Creek and Kakiddi Creek which are situated within the

Stikine River watershed The Stikine River ( ) is a major river in northern British Columbia (BC), Canada and southeastern Alaska in the United States. It drains a large, remote upland area known as the Stikine Country east of the Coast Mountains. Flowing west and so ...

. Mount Edziza consists of several types of

volcanic rock Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and me ...

s and at least six

geological formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock expo ...

s that formed during six distinct stages of

volcanic activity Volcanism, vulcanism, volcanicity, or volcanic activity is the phenomenon where solids, liquids, gases, and their mixtures erupt to the surface of a solid-surface astronomical body such as a planet or a moon. It is caused by the presence of a he ...

. The first stage 1.1 million years ago produced

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

flows and a series of

rhyolite Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture (geology), texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained matri ...

and

trachyte Trachyte () is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and aphanite, aphanitic (fine-grained), with minor amounts of mafic minerals, and is formed by the rapid cooling of lava (or shallow intrus ...

domes. Basalt flows and smaller amounts of trachyte, tristanite,

trachybasalt Trachybasalt is a volcanic rock with a composition between trachyte and basalt. It resembles basalt but has a high content of alkali metal oxides. Minerals in trachybasalt include alkali feldspar, calcic plagioclase, olivine, clinopyroxene and l ...

benmoreite Benmoreite is a volcanic rock of intermediate composition. It is a silica-undersaturated sodium-rich variety of trachyandesite (the other kind is latite) and belongs to the alkaline suite of igneous rocks. It was named after Ben More, a mount ...

and

mugearite Mugearite () is a type of oligoclase-bearing basalt, comprising olivine, apatite, and opaque oxides. The main feldspar in mugearite is oligoclase. Mugearite is a sodium-rich member of the alkaline magma series. In the TAS classification of volc ...

produced during the second stage about 1 million years ago comprise Ice Peak, a glacially eroded

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

forming the south peak of Mount Edziza. The third and fourth stages 0.9 million years ago created basalt

ridge A ridge is a long, narrow, elevated geomorphologic landform, structural feature, or a combination of both separated from the surrounding terrain by steep sides. The sides of a ridge slope away from a narrow top, the crest or ridgecrest, wi ...

s and the central trachyte stratovolcano of Mount Edziza, respectively. Thick trachyte flows were issued during the fifth stage 0.3 million years ago, most of which have since eroded away. The sixth stage began in the last 20,000 years with the eruption of cinder cones, basalt flows and minor trachyte

ejecta Ejecta (; ) are particles ejected from an area. In volcanology, in particular, the term refers to particles including pyroclastic rock, pyroclastic materials (tephra) that came out of a explosive eruption, volcanic explosion and magma eruption v ...

. Renewed

volcanism Volcanism, vulcanism, volcanicity, or volcanic activity is the phenomenon where solids, liquids, gases, and their mixtures erupt to the surface of a solid-surface astronomical body such as a planet or a moon. It is caused by the presence of a he ...

could block local streams with lava flows, disrupt air traffic with

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

and produce floods or

lahar A lahar (, from ) is a violent type of mudflow or debris flow composed of a slurry of Pyroclastic rock, pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a valley, river valley. Lahars are o ...

s from melting glacial ice.

Indigenous peoples There is no generally accepted definition of Indigenous peoples, although in the 21st century the focus has been on self-identification, cultural difference from other groups in a state, a special relationship with their traditional territ ...

have lived adjacent to Mount Edziza for thousands of years and it is a

sacred mountain Sacred mountains are central to certain religions, and are usually the subjects of many legends. For many, the most symbolic aspect of a mountain is the peak because it is believed that it is closest to heaven or other religious realms. Many reli ...

to the

Tahltan The Tahltan or Nahani are a First Nations people of the Athabaskan-speaking ethnolinguistic group who live in northern British Columbia around Telegraph Creek, Dease Lake, and Iskut. The Tahltan constitute the fourth division of the ''Nahan ...

people who historically used

volcanic glass Volcanic glass is the amorphous (uncrystallized) product of rapidly cooling magma. Like all types of glass, it is a state of matter intermediate between the closely packed, highly ordered array of a crystal and the highly disordered array of liqu ...

from it to make tools and weaponry.

Mineral exploration Mining engineering is the extraction of minerals from the ground. It is associated with many other disciplines, such as mineral processing, exploration, excavation, geology, metallurgy, geotechnical engineering and surveying. A mining engineer m ...

just southeast of Mount Edziza had commenced by the 1950s where

gold Gold is a chemical element; it has chemical symbol Au (from Latin ) and atomic number 79. In its pure form, it is a brightness, bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal ...

silver Silver is a chemical element; it has Symbol (chemistry), symbol Ag () and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. ...

and other metals were discovered. This mineral exploration was conducted by several

mining companies This is an incomplete alphabetical list of mining industry, mining companies. A * Adex Mining * Aditya Birla Group * African Rainbow Minerals * Agnico Eagle * Aiteo * Almonty Industries * Alumina Limited, Alumina * Anaconda Copper * Anglo Americ ...

into the early 1990s. Mount Edziza and the surrounding area was made into a large provincial park in the early 1970s to showcase the volcanic landscape. The mountain and

provincial park Ischigualasto Provincial Park A provincial park (or territorial park) is a park administered by one of the provinces of a country, as opposed to a national park. They are similar to state parks in other countries. They are typically open to the ...

can only be accessed by aircraft or by a network of

horse trail A bridle path, also bridleway, equestrian trail, horse riding path, ride, bridle road, or horse trail, is a trail or a thoroughfare that is used by people riding horses, riding on horses. Trails originally created for use by horses often now s ...

s from surrounding roads.

Name and etymology

The mountain was labelled ''Edziza Peak'' on

Geological Survey of Canada The Geological Survey of Canada (GSC; , CGC) is a Canadian federal government agency responsible for performing geological surveys of the country developing Canada's natural resources and protecting the environment. A branch of the Earth Science ...

maps as early as 1926. This name for the mountain was adopted by the

Geographical Names Board of Canada The Geographical Names Board of Canada (GNBC) is a national committee with a secretariat in Natural Resources Canada, part of the Government of Canada, which authorizes the names used and name changes on official federal government maps of Canad ...

on September 24, 1945, as identified on the 1926 Geological Survey of Canada map sheet 309A. ''Edziza Mountain'' appeared in the 1930 BC Gazetteer, in which the name was erroneously spelled ''Edzia''. On December 3, 1974, the form of name was changed from ''Edziza Peak'' to ''Mount Edziza'' in accordance with a 1927 British Columbia Land Surveyors report, two

world aeronautical chart A World Aeronautical Chart (WAC) was a type of aeronautical chart used for navigation by pilots of moderate speed aircraft and aircraft at high altitudes in the United States. They are at a scale of 1:1,000,000 (about 1 inch = 13.7 nautical miles ...

s published in 1950, and three British Columbia maps published in 1931, 1933 and 1943. The form of the name was also changed to reflect entrenched local usage and in conformation with

Mount Edziza Provincial Park Mount Edziza Provincial Park is a provincial park in Cassiar Land District of northern British Columbia, Canada. It was established on 27 July 1972 to showcase the Mount Edziza volcanic complex and the surrounding Tahltan Highland. Geography The ...

, which was established in 1972. To the local

people, Mount Edziza is called , which translates to . A number of explanations have been made regarding the origin of the name ''Edziza''. A 1927 report by J. Davidson of the British Columbia Land Surveyors claims that ''Edziza'' means in the

Tahltan language Tahltan, Tāłtān, also called Tałtan ẕāke ("Tahltan people language"), dah dẕāhge ("our language") or didene keh ("this people’s way") is a poorly documented and endangered Northern Athabaskan language spoken by 235 of the Tahltan, Tah ...

, referring to the deep

deposits or

pumice Pumice (), called pumicite in its powdered or dust form, is a volcanic rock that consists of extremely vesicular rough-textured volcanic glass, which may or may not contain crystals. It is typically light-colored. Scoria is another vesicula ...

-like sand covering large portions of the

around Mount Edziza. According to David Stevenson of

University of Victoria The University of Victoria (UVic) is a public research university located in the municipalities of Oak Bay, British Columbia, Oak Bay and Saanich, British Columbia, Canada. Established in 1903 as Victoria College, British Columbia, Victoria Col ...

's Anthropology Department, or is instead translated as in Tahltan. An explanation listed in the

BC Parks BC Parks is an Government agency, agency of the British Columbia British Columbia Ministry of Environment and Climate Change Strategy, Ministry of Environment and Climate Change Strategy that manages all of the, as of 2020, 1,035 List of British C ...

brochure is that ''Edziza'' means in the Tahltan language. Another explanation proposed by Canadian

volcanologist A volcanologist, or volcano scientist, is a geologist who focuses on understanding the formation and eruptive activity of volcanoes. Volcanologists frequently visit volcanoes, sometimes active ones, to observe and monitor volcanic eruptions, col ...

Jack Souther Jack Gordon Souther (April 25, 1924 – June 1, 2014) was an American Canadian, American-born Canadian geologist, volcanologist, professor and engineer. He contributed significantly to the early understanding of Quaternary, recent volcanic activi ...

is that ''Edziza'' is a

corruption Corruption is a form of dishonesty or a criminal offense that is undertaken by a person or an organization that is entrusted in a position of authority to acquire illicit benefits or abuse power for one's gain. Corruption may involve activities ...

of ''Edzerza'', the name of a local Tahltan family. Obsolete spellings of ''Edziza'' include ''Eddziza'', ''Eddiza'', ''Edidza'', ''Edzia'' and ''Etseza''.

Geography and geomorphology

Location and climate

Mount Edziza rises from within the middle of the Big Raven Plateau, a

barren Barren primarily refers to a state of barrenness (infertility) Barren may also refer to: Places * Barren, Missouri *Barren County, Kentucky *Barren Island (Andaman Islands) * Barren Island, Brooklyn * Barren River Lake Other uses * ''Barren Coun ...

plateau in

bounded on the west by Mess Valley, on the north by Klastline Valley, on the east by Kakiddi Valley and on the south by Chakima and

Walkout In labor disputes, a walkout is a labor strike, the act of employees collectively leaving the workplace and withholding labor as an act of protest. A walkout can also mean the act of leaving a place of work, school, a meeting, a company, or an ...

valleys. It lies at the northern end of the

which also includes the smaller

Arctic Lake Arctic Lake is a man-made lake located by North Sanford, New York. Fish species present in the lake include pumpkinseed sunfish, black bullhead, rainbow trout, and black bass Black is a color that results from the absence or complete ab ...

and Kitsu plateaus to the south. This complex of

shield volcano A shield volcano is a type of volcano named for its low profile, resembling a shield lying on the ground. It is formed by the eruption of highly fluid (low viscosity) lava, which travels farther and forms thinner flows than the more viscous lava ...

es,

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the str ...

s and

s forms a broad, intermontane plateau at the eastern edge of the

, a southeast-trending

upland Upland or Uplands may refer to: Geography *Hill, an area of higher land, generally *Highland, an area of higher land divided into low and high points *Upland and lowland, conditional descriptions of a plain based on elevation above sea level *I ...

area extending along the western side of the

. Mount Edziza is in the

Southern Boreal Plateau Ecosection The Boreal Mountains and Plateaus Ecoregion is a large biogeoclimatic region in northwestern British Columbia, Canada. It is characterized by a complex of rugged mountains and intervening lowlands, and rolling, high plateaus. The ecoregion is boun ...

which consists of several upland summits, wide river valleys and deeply incised plateaus. It is one of seven ecosections comprising the

Boreal Mountains and Plateaus Ecoregion The Boreal Mountains and Plateaus Ecoregion is a large biogeoclimatic region in northwestern British Columbia, Canada. It is characterized by a complex of rugged mountains and intervening lowlands, and rolling, high plateaus. The ecoregion is boun ...

, a large ecological region of northwestern

encompassing high plateaus and rugged mountains with intervening

lowland Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland. Definitions Upland and lowland are portions of a ...

Boreal forest Taiga or tayga ( ; , ), also known as boreal forest or snow forest, is a biome characterized by pinophyta, coniferous forests consisting mostly of pines, spruces, and larches. The taiga, or boreal forest, is the world's largest land biome. I ...

s of

black Black is a color that results from the absence or complete absorption of visible light. It is an achromatic color, without chroma, like white and grey. It is often used symbolically or figuratively to represent darkness.Eva Heller, ''P ...

and

white White is the lightest color and is achromatic (having no chroma). It is the color of objects such as snow, chalk, and milk, and is the opposite of black. White objects fully (or almost fully) reflect and scatter all the visible wa ...

spruce A spruce is a tree of the genus ''Picea'' ( ), a genus of about 40 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal ecosystem, boreal (taiga) regions of the Northern hemisphere. ''Picea'' ...

occur in the lowlands and valley bottoms of this ecoregion whereas

birch A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech- oak family Fagaceae. The genus ''Betula'' contains 3 ...

, spruce and

willow Willows, also called sallows and osiers, of the genus ''Salix'', comprise around 350 species (plus numerous hybrids) of typically deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions. Most species are known ...

form forests on the mid-slopes. Extensive

alpine Alpine may refer to any mountainous region. It may also refer to: Places Europe * Alps, a European mountain range ** Alpine states, which overlap with the European range Australia * Alpine, New South Wales, a Northern Village * Alpine National P ...

altai fescue covers the upper slopes, but barren rock is abundant at higher elevations. The region is characterized by warm summers and cold, snowy winters; temperatures are warmest in mid-summer during the day when they may hit the range. However, temperatures can drop below freezing during summer nights, making snow or freezing rain a possibility at any time of the year. The closest

weather station A weather station is a facility, either on land or sea, with instruments and equipment for measuring atmosphere of Earth, atmospheric conditions to provide information for weather forecasting, weather forecasts and to study the weather and clima ...

s to Mount Edziza are located at

Telegraph Creek Telegraph Creek is a small community located off Highway 37 in northern British Columbia at the confluence of the Stikine River and Telegraph Creek. The only permanent settlement on the Stikine River, it is home to approximately 250 members of ...

and

Dease Lake Dease Lake is a small community in the Cassiar Country of the Northern Interior of British Columbia, Canada. It is 230 km south of the Yukon border on Stewart–Cassiar Highway (Highway 37) at the south end of the lake of the same na ...

, which lie about to the northwest and to the northeast, respectively.

Glaciation

Mount Edziza is covered with snow year-round, containing a long and wide

which covers an area of . Several small

outlet glacier Glacier morphology, or the form a glacier takes, is influenced by temperature, precipitation, topography, and other factors. The goal of glacial morphology is to gain a better understanding of glaciated landscapes and the way they are shaped. T ...

s extending down to elevations of drain the ice cap. Outlet glaciers on the western side of the ice cap spread in broad lobes onto the Big Raven Plateau whereas distributary glaciers on the eastern side drape down steep slopes to form discontinuous

icefall An icefall is a portion of certain glaciers characterized by relatively rapid flow and chaotic crevassed surface, caused in part by gravity. The term ''icefall'' is formed by analogy with the word ''waterfall'', which is a similar phenomenon of ...

s. The Mount Edziza glacier complex is the only one worthy of note on the Stikine Plateau. Four outlet glaciers of the ice cap are named, and all have names of Tahltan origin. Idiji Glacier descends from the eastern side of the ice cap near the

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...

of Tennaya Creek. At the head of Tenchen Creek is Tenchen Glacier, a debris-covered glacier on the eastern side of the ice cap.

Tencho Glacier Tencho Glacier is a mountain glacier in northwestern British Columbia, Canada. It is located inside Mount Edziza Provincial Park on the Tahltan Highland, an upland area of the Stikine Plateau. Tencho Glacier is the source of several small streams ...

at the southern end of the ice cap is the largest outlet glacier. At the head of Tennaya Creek on the eastern side of the ice cap is Tennaya Glacier. As a part of the Mount Edziza volcanic complex, Mount Edziza was covered by a regional ice sheet during the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

which receded and advanced periodically until about 11,000 years ago when

deglaciation Deglaciation is the transition from full glacial conditions during ice ages, to warm interglacials, characterized by global warming and sea level rise due to change in continental ice volume. Thus, it refers to the retreat of a glacier, an ice shee ...

was essentially complete in a steadily warming climate. This warming trend ceased about 2,600 years ago, causing glaciers to advance from Mount Edziza and elsewhere along the volcanic complex as a part of the

neoglaciation The neoglaciation ("renewed glaciation") describes the documented cooling trend in the Earth's climate during the Holocene, following the retreat of the Wisconsin glaciation, the most recent glacial period. Neoglaciation has followed the Hypsither ...

. The present trend towards a more moderate climate put an end to the neoglacial period in the 19th century. This has resulted in rapid glacial recession throughout the Mount Edziza volcanic complex. This rapid glacial recession is apparent from the lack of vegetation on the barren, rocky ground between the glaciers and their

trim line A trim line, also written as trimline, is a clear line on the side of a valley formed by a glacier. The line marks the most recent highest extent of the glacier. The line may be visible due to changes in color to the rock or to changes in vege ...

s which are up to apart.

Structure

Mount Edziza has an elevation of , making it the highest point of the Mount Edziza volcanic complex. It has been considered by some to be the highest or tallest volcano in Canada, but others have given higher elevations of for the Silverthrone volcanic complex in southwestern British Columbia. The nearly flat summit of Mount Edziza contains a circular

that surrounds an ice-filled, in diameter

. This ridge is partially exposed above the ice cap as a discontinuous series of spires and serrated

nunatak A nunatak (from Inuit language, Inuit ) is the summit or ridge of a mountain that protrudes from an ice field or glacier that otherwise covers most of the mountain or ridge. They often form natural pyramidal peaks. Isolated nunataks are also cal ...

s. Spires forming the southern end of the ridge are the highest and consist of greenish grey, sparsely

porphyritic Porphyritic is an adjective used in geology to describe igneous rocks with a distinct difference in the size of mineral crystals, with the larger crystals known as phenocrysts. Both extrusive and intrusive rocks can be porphyritic, meaning ...

. They comprise well-formed, small diameter rock columns that rise nearly vertically more than above the ice cap. Nunataks elsewhere on the summit ridge are more subdued, consisting of

pyroclastic Pyroclast, Pyroclastic or Pyroclastics may refer to: Geology * Pyroclast, or airborne volcanic tephra fragments * Pyroclastic rock, rock fragments produced and ejected by explosive volcanic eruptions * Pyroclastic cone, landform of ejecta fro ...

debris that has been glacially reworked. The eastern side of the ridge has been breached by active

cirque A (; from the Latin word ) is an amphitheatre-like valley formed by Glacier#Erosion, glacial erosion. Alternative names for this landform are corrie (from , meaning a pot or cauldron) and ; ). A cirque may also be a similarly shaped landform a ...

s where remnants of several

lava lake Lava lakes are large volumes of molten lava, usually basaltic, contained in a volcanic vent, crater, or broad depression. The term is used to describe both lava lakes that are wholly or partly molten and those that are solidified (sometim ...

s are exposed inside the crater. Formation of the summit crater was likely caused by a violent eruption at the zenith of the mountain's growth, although it may have also formed during the eruption of the

Kakiddi Formation The Kakiddi Formation is a stratigraphic unit of Pleistocene age in northwestern British Columbia, Canada. Name The Kakiddi Formation is the namesake of Kakiddi Creek, which flows north along the eastern side of the Mount Edziza volcanic complex ...

lava flows or the effusion of voluminous lava during dome construction. Prior to its formation, the summit of the mountain was at least higher than it is today, having possibly risen as a narrower summit cone truncated with a smaller crater. Mt Glenora Stikine Valley 17

The central, high edifice of Mount Edziza is a nearly symmetrical stratovolcano, its symmetry having been broken by several steep-sided lava domes. Its eastern flank has been eroded by a narrow cirque which is bounded by near-vertical

headwall In physical geography and geology, the headwall of a glacier, glacial cirque (landform), cirque is its highest cliff. The term has been more broadly used to describe similar geomorphic features of non-glacial origin consisting of a concave depress ...

s that breach the eastern summit crater rim. A system of radial meltwater

channels Channel, channels, channeling, etc., may refer to: Geography * Channel (geography), a landform consisting of the outline (banks) of the path of a narrow body of water. Australia * Channel Country, region of outback Australia in Queensland and pa ...

has moderately eroded the upper flanks and summit crater rim elsewhere. Lesser modification by erosion has taken place on the southern and northwestern flanks of the stratovolcano. Along the north side of Tenchen Valley on the eastern flank of the stratovolcano are high cliffs exposing explosion

breccia Breccia ( , ; ) is a rock composed of large angular broken fragments of minerals or Rock (geology), rocks cementation (geology), cemented together by a fine-grained matrix (geology), matrix. The word has its origins in the Italian language ...

s, trachyte lavas and

landslide Landslides, also known as landslips, rockslips or rockslides, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, mudflows, shallow or deep-seated slope failures and debris flows. Landslides ...

deposits. Although Mount Edziza is surrounded by relatively flat terrain of the Big Raven Plateau to the north, west and south, the terrain east of the mountain is characterized by a series of ridges with intervening valleys. Among these ridges are Idiji Ridge and

Sorcery Ridge Sorcery Ridge is a mountain ridge extending east of Tencho Glacier on the southern flank of Mount Edziza in northwestern British Columbia, Canada. It is bounded on the north and south by valleys containing unnamed streams while to the east and no ...

which are the namesakes of Idiji Glacier and

Sorcery Creek Sorcery Creek is a tributary of Kakiddi Creek and part of the Stikine River watershed in northwest part of the province of British Columbia, Canada. From high peaks just south of Mount Edziza it flows generally east for roughly Lengths and dista ...

. About south of the summit is Ice Peak, the south peak of Mount Edziza. This prominent pyramid-shaped horn has an elevation of and is the glacially eroded remains of an older stratovolcano whose northern flank is buried under the younger edifice of Mount Edziza. The southern and western flanks are approximal to those of the original stratovolcano whereas the eastern flank has been almost completely destroyed by headward erosion of glacial valleys. At its climax, the stratovolcano had a symmetrical profile and contained a small crater at its summit; the current peak is an erosional remnant etched from the eastern crater rim.

Subfeatures

High on the eastern rim of Ice Peak are two glaciated

volcanic cone Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and s ...

s called Icefall Cone and Ridge Cone, both with elevations of about . Punch Cone on the western flank of Ice Peak protrudes through Mount Edziza's ice cap whereas Koosick Bluff and Ornostay Bluff, also on the western flank of Ice Peak, extend westward onto the surrounding Big Raven Plateau. The northeastern side of Mount Edziza contains

The Pyramid A pyramid is a structure with triangular lateral surfaces converging to an apex. Pyramid may also refer to: Anatomy and medicine * Petrous part of the temporal bone, the pyramid * Pyramid (brainstem), the anterior part of medulla oblongata Gam ...

, a pyramid-shaped lava dome in elevation.

Pillow Ridge Pillow Ridge is a ridge of the Tahltan Highland in northern British Columbia, Canada, located southeast of Telegraph Creek. It extends northwest from Mount Edziza in Mount Edziza Provincial Park. History As its name suggests, Pillow Ridge was na ...

on the northern side of Mount Edziza has an elevation of whereas

Tsekone Ridge Tsekone Ridge, also called Tsekone Peak and Black Knight Cone, is an isolated ridge on the Big Raven Plateau of the Tahltan Highland in northwestern British Columbia, Canada. It is located southeast of Telegraph Creek at the north side of Mount E ...

northwest of Mount Edziza has an elevation of . High on the western side of Mount Edziza is

Triangle Dome Triangle Dome is a trachytic lava dome in northern British Columbia, Canada. It is thought to have formed in the Pleistocene period.Glacier Dome reaches an elevation of on Mount Edziza's lower northeastern flank. Big Raven Plateau labelled 2023

A circular lava dome on the southeastern crater rim of Mount Edziza called

Nanook Dome Nanook Dome is a rounded mass of rock on the southeastern rim of Mount Edziza's summit crater in northwestern British Columbia, Canada. It has an elevation of , slightly lower than the pinnacles on the southern crater rim which represent the hi ...

has an elevation of . Sphinx Dome, in elevation, is a partially buried lava dome on the northeastern flank of Mount Edziza. Remnants of a volcanic pile called

Pharaoh Dome Pharaoh Dome is a lava dome in northwestern British Columbia, Canada, located near Mount Edziza in Mount Edziza Provincial Park. It last erupted during the Pleistocene epoch.Cinder Cliff is a high barrier of

s on the eastern side of Mount Edziza at an elevation of in the north fork of Tenchen Creek. The Neck, in elevation, is a circular

volcanic plug A volcanic plug, also called a volcanic neck or lava neck, is a volcano, volcanic object created when magma hardens within a Volcanic vent, vent on an active volcano. When present, a plug can cause an extreme build-up of high gas pressure if risi ...

on the southeastern flank of Ice Peak. The

Snowshoe Lava Field The Snowshoe Lava Field (SLF) is a largely buried volcanic field at Mount Edziza in British Columbia, Canada. It reaches an elevation of and engulfs more than of the Big Raven Plateau and adjacent valleys with blocky lava flows. The Snowshoe L ...

on the west flank of lce Peak contains at least 12 volcanic cones, a handful of which are named. Tennena Cone is a symmetrical volcanic cone high on the west side of Ice Peak. It has an elevation of and is almost completely surrounded by ice.

Cocoa Crater Cocoa Crater, sometimes called Cocoa Cone, is a cinder cone in Cassiar Land District of northwestern British Columbia, Canada. It has an elevation of and is one of several volcanic cones in the Snowshoe Lava Field at the southern end of the ...

is the largest cone in the Snowshoe Lava Field and is in elevation. To the southeast is Coffee Crater which has an elevation of . Keda Cone, in elevation, lies just south of Coffee Crater on the south side of upper Taweh Creek. A

saucer A saucer is a type of small dishware. While in the Middle Ages a saucer was used for serving condiments and sauces, currently the term is used to denote a small plate or shallow bowl that supports a cup – usually one used to serve coffee t ...

-shaped mound of lava called

The Saucer The Saucer is a cinder cone in northern British Columbia, Canada. It is thought to have last erupted in the Holocene epoch.Desolation Lava Field The Desolation Lava Field (DLF) is a volcanic field at Mount Edziza in British Columbia, Canada. It reaches an elevation of on the Big Raven Plateau, but decreases to at Buckley Lake and in the Klastline River valley. The lava field cover ...

on the northern flank of Mount Edziza contains at least 10 cinder cones, most of which are clustered near the northern

of Mount Edziza's ice cap. Sleet Cone and

Storm Cone Storm Cone is a cinder cone in northern British Columbia, Canada. It is thought to have last erupted in the Holocene period and lies on the Desolation lava field which is part of the Mount Edziza volcanic complex.Triplex Cones The Triplex Cones are a group of three cinder cones in northern British Columbia, Canada. They are thought to have last erupted during the Holocene epoch.Twin Cone, in elevation, is a

pyroclastic cone Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and s ...

whose southeastern side has been breached. Moraine Cone has an elevation of nearly and has been nearly destroyed by alpine glaciation. The northeastern side of Mount Edziza contains Williams Cone, a prominent cinder cone in elevation.

Eve Cone Eve Cone, sometimes referred to as Eve's Cone, is a cinder cone in Cassiar Land District of northwestern British Columbia, Canada. It has an elevation of and is one of several volcanic cones in the Desolation Lava Field at the northern end of t ...

, in elevation, is a symmetrical cone between Buckley Lake and Mount Edziza. The northernmost cinder cone in the Desolation Lava Field is

Sidas Cone Sidas Cone is a cinder cone on the Big Raven Plateau at the northern end of Mount Edziza Provincial Park in British Columbia, Canada. Its name, meaning "cut oneself with a knife" in the Tahltan language, is descriptive of the breach that has cut ...

which consists of two symmetrical halves and reaches an elevation of .

Drainage

Mount Edziza is drained on all sides by streams within the

. Elwyn Creek is a westward-flowing stream originating from the northwestern flank of Mount Edziza. It contains one named

tributary A tributary, or an ''affluent'', is a stream or river that flows into a larger stream (''main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which they ...

Kadeya Creek Kadeya Creek is a tributary of Elwyn Creek, which in turn is a tributary of Mess Creek, part of the Stikine River watershed in northwest part of the province of British Columbia, Canada. It flows generally northwest for roughly to join Elwyn Cr ...

, which flows northwest from Mount Edziza. Sezill Creek is a westward-flowing stream originating from the western flank of Mount Edziza. It is a tributary of Taweh Creek which flows northwest from just south of Mount Edziza. Elwyn Creek and Taweh Creek are tributaries of Mess Creek which flows northwestward into the Stikine River. Tsecha Creek is a northeast-flowing stream originating from the northern flank of Mount Edziza. Nido Creek flows northeastward from the eastern side of Mount Edziza into Nuttlude Lake. Flowing from the eastern flank of Mount Edziza just southeast of The Pyramid is Tenchen Creek. Shaman Creek flows east and north into Kakiddi Lake from the southern flank of Mount Edziza. Tennaya Creek flows northeastward from the eastern side of Mount Edziza into Nuttlude Lake. All five streams are tributaries of Kakiddi Creek, a north-flowing tributary of the Klastline River which flows north into the Stikine River.

Geology

Background

Mount Edziza is part of the

Northern Cordilleran Volcanic Province The Northern Cordilleran Volcanic Province (NCVP), 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. This belt of volcanoes ex ...

, a broad area of shield volcanoes, lava domes, cinder cones and stratovolcanoes extending from northwestern British Columbia northwards through

Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...

into easternmost

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

. The dominant rocks comprising these volcanoes are

alkali basalt Alkali basalt or alkali olivine basalt is a dark-colored, porphyritic volcanic rock usually found in oceanic and continental areas associated with volcanic activity, such as oceanic islands, continental rifts and volcanic fields. Alkali basalt i ...

s and

hawaiite Hawaiite is an olivine basalt with a composition between alkali basalt and mugearite. It was first used as a name for some lavas found on the island of Hawaii. It occurs during the later stages of volcanic activity on oceanic islands such as Ha ...

s, but

nephelinite Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite). If olivine is present, the rock may be classified as an olivine nephelinite. Nephelinite is dark in color and may rese ...

basanite Basanite () is an igneous, volcanic ( extrusive) rock with aphanitic to porphyritic texture. It is composed mostly of feldspathoids, pyroxenes, olivine, and calcic plagioclase and forms from magma low in silica and enriched in alkali metal ox ...

and

peralkaline Peralkaline rocks include those igneous rocks which have a deficiency of aluminium such that sodium and potassium are in excess of that needed for feldspar. The presence of aegerine (sodium pyroxene) and riebeckite (sodium amphibole) are indicat ...

phonolite Phonolite is an uncommon shallow intrusive or extrusive rock, of intermediate chemical composition between felsic and mafic, with texture ranging from aphanitic (fine-grained) to porphyritic (mixed fine- and coarse-grained). Phonolite is a var ...

, trachyte and

comendite Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite. Phenocrysts are sodic sanidine with minor albite and bipyramidal quartz. Iddings, Joseph Paxson, 1913, ''Igneous rocks: composition, texture and classification'', v ...

are locally abundant. These rocks were deposited by volcanic eruptions from 20 million years ago to as recently as a few hundred years ago. The cause of

in the Northern Cordilleran Volcanic Province is thought to be due to

rift In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben ...

ing of the

North American Cordillera The North American Cordillera, sometimes also called the Western Cordillera of North America, the Western Cordillera, or the Pacific Cordillera, is the North American portion of the American Cordillera, the mountain chain system along the Pacifi ...

driven by changes in relative

plate motion Plate may refer to: Cooking * Plate (dishware), broad, mainly flat vessel commonly used to serve food * Plates, tableware, dishes or dishware used for setting a table, serving food and dining * Plate, the content of such a plate (for example: r ...

between the

North American North America is a continent in the Northern and Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the sou ...

and

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the cont ...

plates.

Composition

A wide variety of volcanic rocks comprise Mount Edziza, the main

mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...

rock being

which comprises lava flows, cinder cones and ash

beds A bed is a piece of furniture that is used as a place to sleep, rest, and relax. Most modern beds consist of a soft, cushioned mattress on a bed frame. The mattress rests either on a solid base, often wood slats, or a sprung base. Many be ...

on the flanks of the mountain. Basalt at Mount Edziza is in the form of alkali basalt and hawaiite; the latter is thought to be the product of partial

fractional crystallization Fractional crystallization may refer to: * Fractional crystallization (chemistry), a process to separate different solutes from a solution * Fractional crystallization (geology) Fractional crystallization, or crystal fractionation, is one of the ...

in subterranean

magma chamber A magma chamber is a large pool of liquid rock beneath the surface of the Earth. The molten rock, or magma, in such a chamber is less dense than the surrounding country rock, which produces buoyant forces on the magma that tend to drive it u ...

s. Volcanic rocks of

intermediate composition In igneous petrology, an intermediate composition refers to the chemical composition of a rock that has 51.563 wt% SiO2 being an intermediate between felsic and mafic compositions. Typical intermediate rocks include andesite and trachyandesite ...

such as

, tristanite,

and

are restricted to Ice Peak where they form the upper part of this subsidiary peak. Ice Peak is the only location where mugearites and benmoreites are found in the Mount Edziza volcanic complex.

Felsic In geology, felsic is a grammatical modifier, modifier describing igneous rocks that are relatively rich in elements that form feldspar and quartz.Marshak, Stephen, 2009, ''Essentials of Geology,'' W. W. Norton & Company, 3rd ed. It is contrasted ...

volcanic rocks such as trachyte and

form the central stratovolcano of Mount Edziza, the upper part of Ice Peak and several lava domes and flows, as well as pyroclastic rocks.

Stratigraphy

Mount Edziza is subdivided into at least six

s, each the product of a distinct stage of volcanic activity. These periods of volcanic activity occurred during four magmatic cycles of the Mount Edziza volcanic complex; each cycle began with the effusion of alkali basalt and culminated with the eruption of lesser volumes of felsic magma. The oldest geological formation comprising Mount Edziza is the Pyramid Formation, which formed during a period of volcanic activity 1.1 million years ago at the end of the second magmatic cycle. Another period of volcanic activity about 1 million years ago during the start of the third magmatic cycle deposited the

Ice Peak Formation The Ice Peak Formation (IPF) is a stratigraphic unit of Pleistocene age in northwestern British Columbia, Canada. It is the seventh youngest and fifth most voluminous of the 13 recognized geological formations comprising the Mount Edziza volcanic ...

on the southern part of the Pyramid Formation. The third and fourth oldest geological formations comprising Mount Edziza are the Pillow Ridge and Edziza formations, which were deposited by volcanic eruptions 0.9 million years ago during the later stages of the third magmatic cycle; they both overlie the Ice Peak Formation. A period of volcanic activity at the end of the fourth magmatic cycle 0.3 million years ago deposited the Kakiddi Formation, the fifth oldest geological formation comprising Mount Edziza which also overlies the Ice Peak Formation. The youngest geological formation is the

Big Raven Formation The Big Raven Formation is a stratigraphic unit of Quaternary age in northwestern British Columbia, Canada. It is the youngest and least voluminous geological formation of the Mount Edziza volcanic complex (MEVC); it overlies at least eight older ...

, which was formed by a period of volcanic activity during the fifth magmatic cycle in the last 20,000 years.

Pyramid Formation

The Pyramid Formation is exposed along the deeply eroded eastern flank of Mount Edziza where rhyolite and trachyte flows, domes and pyroclastic rocks of this formation comprise ridges and prominent cliffs. A basaltic lava flow sequence up to thick overlies the basal trachytic

surge Surge means a sudden transient rush or flood, and may refer to: Science * Storm surge, the onshore flow of water associated with a low-pressure weather system * Surge (glacier), a short-lived event where a glacier can move up to velocities 100 t ...

deposit of the Pyramid Formation; it is included as a part of this formation due to it being coeval with the early stages of Pyramid felsic volcanism. Potassium–argon dating of the Pyramid Formation has yielded ages of 1.2 ± 0.4 million years and 1.2 ± 0.03 million years from comenditic

glass Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window pane ...

, as well as 0.94 ± 0.12 million years and 0.94 ± 0.05 million years from trachyte. The Pyramid Formation includes Sphinx Dome, Pharaoh Dome and The Pyramid which were the main sources of the rhyolites and trachytes of this geological formation. The Pyramid is a prominent trachyte dome whose structure has not been greatly modified by erosion, nor has it been buried under younger lavas. In contrast, much of the southern edge of Sphinx Dome has been destroyed by headward erosion of Cook Creek; the western half of this rhyolite dome is also buried under trachyte of the Edziza Formation. From Cartoona Ridge north to Tennaya Creek are isolated remnants of Pharaoh Dome, the main mass of which comprises flow-layered rhyolite and is buried under basalt of the Ice Peak Formation.

Ice Peak Formation

The Ice Peak Formation consists of lava and pyroclastic rocks that originated mainly from Ice Peak about south of the summit of Mount Edziza. Two

stratigraphic unit A stratigraphic unit is a volume of rock of identifiable origin and relative age range that is defined by the distinctive and dominant, easily mapped and recognizable petrographic, lithologic or paleontologic features ( facies) that characteriz ...

s comprise this once symmetrical stratovolcano, both of which are

lithologically The lithology of a rock unit is a description of its physical characteristics visible at outcrop, in hand or core samples, or with low magnification microscopy. Physical characteristics include colour, texture, grain size, and composition. Lith ...

distinct. The lower stratigraphic unit, which forms much of the volcanic pile, is an assemblage of mostly thin basalt flows. Lavas of intermediate composition such as tristanite, trachybasalt and mugearite are very limited in extent. The upper stratigraphic unit is a highly varied succession of lavas and pyroclastic rocks forming the high, central edifice of Ice Peak. It consists of basalt, trachyte and a variety of intermediate rocks such as tristanite, trachybasalt, benmoreite and mugearite. Edziza042909-- 066-15

The Ice Peak Formation also includes the Koosick and Ornostay bluffs, both of which are thick lobes of trachyte that originated under the summit ice cap. Both bluffs are similar in

geomorphology Geomorphology () is the scientific study of the origin and evolution of topographic and bathymetric features generated by physical, chemical or biological processes operating at or near Earth's surface. Geomorphologists seek to understand wh ...

and composition, consisting of several lava flows up to thick. The Neck, which forms a prominent high

buttress A buttress is an architectural structure built against or projecting from a wall which serves to support or reinforce the wall. Buttresses are fairly common on more ancient (typically Gothic) buildings, as a means of providing support to act ...

on Sorcery Ridge, is also part of the Ice Peak Formation. Potassium–argon dating of

pantelleritic Pantellerite is a type of volcanic rock, specifically a peralkaline rhyolite. It has a higher iron and lower aluminium composition than comendite. It is named after Pantelleria, a volcanic island in the Strait of Sicily and the type location for ...

trachyte from the Ice Peak Formation has yielded ages of 1.6 ± 0.2 million years, 1.5 ± 0.4 million years and 1.5 ± 0.1 million years. These dates being older than those of the Pyramid Formation may be due to excess

argon Argon is a chemical element; it has symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third most abundant gas in Earth's atmosphere, at 0.934% (9340 ppmv). It is more than twice as abu ...

in the Ice Peak Formation and are therefore considered unreliable. Ice Peak Formation basalt flows on the northwestern flank of Mount Edziza are

interbedded In geology, interbedding occurs when beds (layers of rock) of a particular lithology lie between or alternate with beds of a different lithology. For example, sedimentary rocks may be interbedded if there were sea level variations in their sedimen ...

with

diamictite Diamictite (; from Ancient Greek (): 'through' and (): 'mixed') is a type of lithified sedimentary rock that consists of nonsorted to poorly sorted terrigenous sediment containing particles that range in size from clay to boulders, suspended ...

s recording a regional glaciation that occurred during the

Early Pleistocene The Early Pleistocene is an unofficial epoch (geology), sub-epoch in the international geologic timescale in chronostratigraphy, representing the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently esti ...

. The lowermost basalt flow contains basal

pillows A pillow is a support of the body at rest for comfort, therapy, or decoration. Pillows are used in different variations by many species, including humans. Some types of pillows include throw pillows, body pillows, decorative pillows, and many ...

, directly overlies

hyaloclastite Hyaloclastite is a volcanoclastic accumulation or breccia consisting of glass (from the Greek ''hyalus'') fragments (clasts) formed by quench fragmentation of lava flow surfaces during submarine or subglacial extrusion. It occurs as thin marg ...

s and is brecciated and deformed, suggesting it may have been extruded onto a glacier or an

ice sheet In glaciology, an ice sheet, also known as a continental glacier, is a mass of glacier, glacial ice that covers surrounding terrain and is greater than . The only current ice sheets are the Antarctic ice sheet and the Greenland ice sheet. Ice s ...

. Its extrusion onto glacial ice is also evident due to the lack of

fluvial A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it ru ...

and

lacustrine A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from t ...

sediments at the base of the basalt flow which suggests it did not extrude into lakes or streams. The steep sides and unusually large thicknesses of the trachyte flows comprising Koosick and Ornostay bluffs is attributed to them having been extruded through glacial ice.

Pillow Ridge Formation

The Pillow Ridge Formation is restricted to Pillow Ridge and Tsekone Ridge on Mount Edziza's northwestern flank, both of which are glaciovolcanic in origin. Pillow Ridge is a nearly long, northwesterly-trending ridge of basaltic pillow lava, pillow breccia,

tuff breccia Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock cont ...

and

dikes Dyke or dike may refer to: General uses * Dyke (slang), a slang word meaning "lesbian" * Dike (geology), formations of magma or sediment that cut through and across the layering of adjacent rocks * Dike (mythology), ''Dikē'', the Greek goddess ...

. Its upper surface is sparsely covered by trachyte of the Edziza Formation whereas the western edge of the ridge overlaps with a large flow of Edziza trachyte. Tsekone Ridge is an isolated volcanic pile adjacent to Pillow Ridge consisting of basaltic pillow lava and tuff breccia that has been cut by vertical north-trending feeder dikes. This ridge is elliptical in structure, containing a nearly long, north–south trending axis. Nearly surrounding Tsekone Ridge are trachyte flows of the Edziza Formation which is slightly younger than the Pillow Ridge Formation.

Fission track dating Fission track dating is a radiometric dating technique based on analyses of the damage trails, or tracks, left by fission fragments in certain uranium-bearing minerals and glasses. Fission-track dating is a relatively simple method of radiometr ...

apatite Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of Hydroxide, OH−, Fluoride, F− and Chloride, Cl− ion, respectively, in the crystal. The formula of the admixture of ...

from partially fused

granitic A granitoid is a broad term referring to a diverse group of coarse-grained igneous rocks that are widely distributed across the globe, covering a significant portion of the Earth's exposed surface and constituting a large part of the continental ...

xenolith A xenolith ("foreign rock") is a rock (geology), rock fragment (Country rock (geology), country rock) that becomes enveloped in a larger rock during the latter's development and solidification. In geology, the term ''xenolith'' is almost exclusi ...

s in contaminated Pillow Ridge Formation basalt has yielded ages of 0.9 ± 0.3 million years and 0.8 ± 0.25 million years. In contrast, potassium–argon dating has yielded an anomalously old age of 5.9 ± 0.9 million years which is inconsistent with the ages of the underlying and overlying formations. This date being much older than the fission track dates most likely results from contamination and introduction of excess argon from the partially fused granitic and gneissic xenoliths in Pillow Ridge Formation basalt.

Edziza Formation

The Edziza Formation consists mainly of trachyte that straddles the pantelleritic trachyte and comenditic trachyte boundary. It includes the central stratovolcano of Mount Edziza, as well as several satellitic features on its summit and flanks. Inside the summit crater of the stratovolcano is a succession of at least four lava lakes exposed in the breached eastern crater rim. They are represented by at least four cooling units, the lower two of which are about thick. The two upper cooling units reach thicknesses of about and may have originated from Nanook Dome, the largest of three lava domes consisting of Edziza Formation trachyte. Nanook Dome is about in diameter whose structure appears to be nearly identical to its original form. The other two Edziza Formation trachyte domes, Glacier Dome and Triangle Dome, are elliptical in structure and contain concentric flow layering. Potassium–argon dating of pantelleritic trachyte or comenditic trachyte from the Edziza Formation has yielded an age of 0.9 ± 0.3 million years.

Kakiddi Formation

The Kakiddi Formation consists of the remains of thick trachyte flows and associated pyroclastic rocks. They are lithologically and geomorphologically similar to Edziza Formation trachytes, but occur south of the central stratovolcano of Mount Edziza. The remains of a nearly wide, rubble-covered trachyte flow are present on the eastern flank of Ice Peak in Sorcery Valley and in the south fork of Tennaya Valley where it is divided into two tributary branches. In Kakiddi Valley, the lava flow appears to have spread out to form a once continuous, terminal lobe at least wide. Remnants of this terminal lobe are present in the form of isolated

outcrop An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth and other terrestrial planets. Features Outcrops do not cover the majority of the Earth's land surface because in most p ...

s adjacent to Kakiddi Lake and Nuttlude Lake. The source of this Kakiddi flow remains unknown, but the tributary branch that descended Tennaya Valley probably originated from a vent near the summit of Ice Peak that is now covered by glaciers. Another plausible source is Nanook Dome on the southeastern crater rim of Mount Edziza. A relatively small trachyte flow descended from Punch Cone on the western flank of Ice Peak and spread onto the Big Raven Plateau. Potassium–argon dating of the Kakiddi Formation has yielded ages of 0.31 ± 0.07 million years from mugearite, as well as 0.30 ± 0.02 million years, 0.29 ± 0.02 million years and 0.28 ± 0.02 million years from trachyte.

Big Raven Formation

The Big Raven Formation includes the Desolation Lava Field, the Snowshoe Lava Field, Icefall Cone, Ridge Cone, Cinder Cliff and the

Sheep Track Member The Sheep Track Member is a stratigraphic unit of the Big Raven Formation, part of the Mount Edziza volcanic complex in northwestern British Columbia, Canada. It consists of pumice from an explosive eruption that fell over an area about . The pu ...

. All of these features consist of alkali basalt and hawaiite with the exception of the Sheep Track Member which comprises a small volume of trachyte pumice. Some of the lava flows comprising the Desolation Lava Field issued from vents adjacent to the northern trim line of the summit ice cap where meltwater interacted with the erupting lava to form

tuff ring Phreatomagmatic eruptions are volcanic eruptions resulting from interaction between magma and water. They differ from exclusively magmatic eruptions and phreatic eruptions. Unlike phreatic eruptions, the products of phreatomagmatic eruptions cont ...

s. These tuff rings, composed of quenched breccia, later transitioned into normal

subaerial In natural science, subaerial (literally "under the air") has been used since 1833,Subaerial
in the Merriam- ...

cinder cones as the progressing eruptions displaced ice and meltwater. The Snowshoe Lava Field contains subglacial and subaerial cones, as well as transitional cones which consist of both subaqueous and subaerial

. Eruptions on the heavily eroded eastern flank of Mount Edziza created Icefall Cone, Ridge Cone and Cinder Cliff which comprise a separate volcanic zone called the east slope centres. The Sheep Track Member is the product of an

explosive eruption In volcanology, an explosive eruption is a volcanic eruption of the most violent type. A notable example is the 1980 eruption of Mount St. Helens. Such eruptions result when sufficient gas has dissolved under pressure within a Viscosity, viscous ...

that originated from the southwestern flank of Ice Peak. It was deposited on all lava flows and cinder cones in the Snowshoe Lava Field with the exception of The Saucer which likely postdates the Sheep Track eruption. The source of the Sheep Track pumice is unknown, but it probably originated from a vent hidden under Tencho Glacier.

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

in age, the Big Raven Formation has yielded dates of 6520 BCE ± 200 years, 750 BCE ± 100 years, 610 CE ± 150 years and 950 CE ± 6000 years.

Basement

Underlying the aforementioned geological formations is the Tenchen Member of the

Nido Formation The Nido Formation is a stratigraphic unit of Neogene age in northwestern British Columbia, Canada. Name The Nido Formation takes its name from Nido Creek, a stream flowing northeast from the eastern flank of Mount Edziza into Nuttlude Lake. Nid ...

, one of many stratigraphic units forming the Big Raven Plateau. Basalt flows and pyroclastic rocks of this

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58geological member Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth s ...

are exposed north of Raspberry Pass on the eastern and western flanks of Mount Edziza. Much of the Tenchen Member as well as the southern edge of the Ice Peak volcanic pile are underlain by the Armadillo Formation which consists of

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

comendite, trachyte and alkali basalt. Most of Mount Edziza is also underlain by Miocene basalt flows of the

Raspberry Formation The Raspberry Formation is a stratigraphic unit of Miocene age in northwestern British Columbia, Canada. Name The Raspberry Formation takes its name from Raspberry Pass, a mountain pass cutting through the central portion of the Mount Edziza volc ...

which form the base of prominent

escarpment An escarpment is a steep slope or long cliff that forms as a result of faulting or erosion and separates two relatively level areas having different elevations. Due to the similarity, the term '' scarp'' may mistakenly be incorrectly used inte ...

s east and west of the mountain. These geological formations are underlain by the

Stikinia Stikinia, or the Stikine terrane, is a terrane in British Columbia, Canada; the largest of the Canadian Cordillera. It formed as an independent, intraoceanic volcanic arc during the Paleozoic and Mesozoic. Stikinia forms the bedrock of numerous ...

terrane In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its d ...

, a

Paleozoic The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma a ...

and

Mesozoic The Mesozoic Era is the Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Period (geology), Periods. It is characterized by the dominance of archosaurian r ...

suite Suite may refer to: Arts and entertainment *Suite (music), a set of musical pieces considered as one composition ** Suite (Bach), a list of suites composed by J. S. Bach ** Suite (Cassadó), a mid-1920s composition by Gaspar Cassadó ** ''Suite' ...

of volcanic and

sedimentary Sedimentary rocks are types of rock formed by the cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or deposited at Earth's surface. Sedime ...

rocks that accreted to the

continental margin A continental margin is the outer edge of continental crust abutting oceanic crust under coastal waters. It is one of the three major zones of the ocean floor, the other two being deep-ocean basins and mid-ocean ridges. The continental marg ...

of North America during the

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

Hazards and monitoring

Natural Resources Canada Natural Resources Canada (NRCan; ; )Natural Resources Canada is the applied title under the Federal Identity Program; the legal title is Department of Natural Resources (). is the department of the Government of Canada responsible for natural r ...

report published in 2021 considers Mount Edziza a high threat volcano because it has had the highest eruption rate in Canada throughout the Holocene. However, its extremely remote location makes it less

hazardous A hazard is a potential source of harm. Substances, events, or circumstances can constitute hazards when their nature would potentially allow them to cause damage to health, life, property, or any other interest of value. The probability of that ...

than

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 Ri ...

, Mount Price,

Mount Cayley Mount Cayley is an eroded but potentially active stratovolcano in the Pacific Ranges of southwestern British Columbia, Canada. Located north of Squamish and west of Whistler, the volcano resides on the edge of the Powder Mountain Icefield. ...

and Mount Meager in southwestern British Columbia. The hazard rating of Mount Edziza is similar to that of

Mount Churchill Mount Churchill is a dormant volcano in the Saint Elias Mountains and the Wrangell Volcanic Field (WVF) of eastern Alaska. Churchill and its neighbor Mount Bona are both ice-covered volcanoes with Churchill having a caldera just east of its ...

in the U.S. state of Alaska which deposited the White River Ash across northwestern Canada in the last 2,000 years. Lava flows are a potential hazard at Mount Edziza as they have formerly dammed local streams. Another potential hazard is the ignition of wildfires by eruptions since the surrounding area contains vegetation. An eruption under the ice cap could produce floods or lahars that may flow into the Stikine or

Iskut Iskut is a small, mostly Indigenous community in the Stikine Country of northwestern British Columbia. It is located on Highway 37, at the north end of Eddontenajon Lake just south of Dease Lake and the crossing of the Stikine River. Communi ...

rivers, potentially destroying

salmon run A salmon run is an annual fish migration event where many salmonid species, which are typically hatched in fresh water and live most of their adult life downstream in the ocean, swim back against the stream to the upper reaches of rivers to s ...

s and threatening

river bank In geography, a bank is the land alongside a body of water. Different structures are referred to as ''banks'' in different fields of geography. In limnology (the study of inland waters), a stream bank or river bank is the terrain alongsid ...

villages.

Mount Edziza trachyte and rhyolite have

silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant f ...

-rich compositions that are comparable to those associated with the most powerful eruptions around the world; parts of northwestern Canada could be affected by an

ash column An eruption column or eruption plume is a cloud of super-heated ash and tephra suspended in gases emitted during an explosive volcanic eruption. The volcanic materials form a vertical column or plume that may rise many kilometers into the air ...

if an explosive eruption were to happen from the volcano. Ash columns can drift for thousands of kilometres downwind and often become increasingly spread out over a larger area with increasing distance from an erupting vent. Mount Edziza lies under a major

air route In the United States, airways or air routes are defined by the Federal Aviation Administration, Federal Aviation Administration (FAA) in two ways: "VOR Federal airways and Low/Medium Frequency (L/MF) (Colored) Federal airways" These are desi ...

from

Vancouver Vancouver is a major city in Western Canada, located in the Lower Mainland region of British Columbia. As the List of cities in British Columbia, most populous city in the province, the 2021 Canadian census recorded 662,248 people in the cit ...

, British Columbia to

Whitehorse Whitehorse () is the capital of Yukon, and the largest city in Northern Canada. It was incorporated in 1950 and is located at kilometre 1426 (Historic Mile 918) on the Alaska Highway in southern Yukon. Whitehorse's downtown and Riverdale areas ...

, Yukon, suggesting the volcano poses a potential threat to air traffic. Volcanic ash reduces visibility and can cause jet engine failure, as well as damage to other aircraft systems. Like other volcanoes in Canada, Mount Edziza is not monitored closely enough by the Geological Survey of Canada to ascertain its activity level. The

Canadian National Seismograph Network The Canadian National Seismograph Network (CNSN) is a network of seismographs to detect earthquakes across Canada. It is operated by Natural Resources Canada Natural Resources Canada (NRCan; ; )Natural Resources Canada is the applied title under ...

has been established to monitor earthquakes throughout Canada, but it is too far away to provide an accurate indication of activity under the mountain. It may sense an increase in seismic activity if Mount Edziza becomes highly restless, but this may only provide a warning for a large eruption; the system might detect activity only once the volcano has started erupting. If Mount Edziza were to erupt, mechanisms exist to orchestrate relief efforts. The

Interagency Volcanic Event Notification Plan The Interagency Volcanic Event Notification Plan (IVENP) is a program in Canada established to outline the notification procedure of some of the main agencies that would be involved in response to a volcanic eruption in Canada, an eruption close to ...

was created to outline the notification procedure of some of the main agencies that would respond to an erupting volcano in Canada, an eruption close to the

Canada–United States border The international border between Canada and the United States is the longest in the world by total length. The boundary (including boundaries in the Great Lakes, Atlantic, and Pacific coasts) is long. The land border has two sections: Canada' ...

or any eruption that would affect Canada.

Human history

Indigenous peoples

Mount Edziza lies within the traditional territory of the Tahltan people which covers an area of more than . Historically, Mount Edziza and other volcanoes of the Mount Edziza volcanic complex were sources of

obsidian Obsidian ( ) is a naturally occurring volcanic glass formed when lava extrusive rock, extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock. Produced from felsic lava, obsidian is rich in the lighter element ...

for the Tahltan people. This volcanic glass was used in the manufacturing of projectile points and cutting blades which were widely traded throughout the

Pacific Northwest The Pacific Northwest (PNW; ) is a geographic region in Western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though no official boundary exists, the most common ...

. Artifacts made of Edziza obsidian have been recovered from

archaeological site An archaeological site is a place (or group of physical sites) in which evidence of past activity is preserved (either prehistoric or recorded history, historic or contemporary), and which has been, or may be, investigated using the discipline ...

s over an area of more than across Alaska,

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

, Yukon and the

British Columbia Coast The British Columbia Coast, popularly referred to as the BC Coast or simply the Coast, is a geographic region of the Provinces and territories of Canada, Canadian province of British Columbia. As the entire western continental coastline of Canada ...

, making it the most widely distributed obsidian in western North America. The Hidden Falls archaeological site in Alaska has yielded a hydration date of 10,000 years for Edziza obsidian, suggesting the area was being exploited as an obsidian source soon after ice sheets of the Last Glacial Period retreated. Tahltan dancers

Two obsidian flows of the Pyramid Formation occur on The Pyramid and are exposed as two outcrops; they were quarried as evidenced by the occurrence of this obsidian in at least five

s outside of Tahltan territory. The Ice Peak Formation contains two obsidian flows on Sorcery Ridge that were also exploited as an obsidian source. Sorcery Ridge obsidian occurs in at least two archaeological sites outside of Tahltan territory. In or before 1974, two Tahltan men named Johnny Edzerza and Hank Williams were killed in an

avalanche An avalanche is a rapid flow of snow down a Grade (slope), slope, such as a hill or mountain. Avalanches can be triggered spontaneously, by factors such as increased precipitation or snowpack weakening, or by external means such as humans, othe ...

while they were crossing the mountain. Edzerza was buried on Mount Edziza, but his surname was erroneously spelled "Edzertza" on his grave marker. Williams Cone on the northeastern side of Mount Edziza was named in honour of Hank Williams whereas Eve Cone between Mount Edziza and Buckley Lake was named in honour of Johnny Edzerza's wife, Eve Brown Edzerza. Mount Edziza continues to be an important cultural resource for the Tahltan people. In 2021, Chad Norman Day, president of the Tahltan Central Government, said "Mount Edziza and the surrounding area has always been sacred to the Tahltan Nation. The obsidian from this portion of our territory provided us with weaponry, tools and trading goods that ensured our Tahltan people could thrive for thousands of years."

Mineral exploration

Just southeast of Mount Edziza was an area once known as the Spectrum property, a block of mineral claims that covered

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tet ...

pyrite The mineral pyrite ( ), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic luster and pale brass-yellow hue ...

and

chalcopyrite Chalcopyrite ( ) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a Mohs scale, hardness of 3.5 to 4 ...

mineralization in fractured sedimentary and volcanic rocks of

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch a ...

age. Commodities on the property included

copper Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orang ...

lead Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...

and

zinc Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic tabl ...

on the Spectrum property began as early as 1957 when Torbit Silver Mines performed surface work on the gold-bearing Hawk

vein Veins () are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and feta ...

. This was followed by drilling of the Hawk vein by Shawnigan Mining and Smelting in 1967. Exploration by Mitsui Mining and Smelting in 1970 involved

geophysical Geophysics () is a subject of natural science concerned with the physical processes and properties of Earth and its surrounding space environment, and the use of quantitative methods for their analysis. Geophysicists conduct investigations acros ...

and geochemical surveying. From 1971 to 1973,

Imperial Oil Imperial Oil Limited () is a Canadian petroleum company. It is Canada's second-largest integrated oil company. It is majority-owned by American oil company ExxonMobil, with a 69.6% ownership stake in the company. It is a producer of crude oil, ...

conducted geophysical,

geological Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth s ...

and geochemical surveying, as well as of drilling in four holes. Between 1976 and 1981, geochemical and geological surveys were conducted on the Spectrum property by Consolidated Silver Ridge Mines and Newhawk Mines. Consolidated Silver Ridge Mines built an

airstrip An aerodrome, airfield, or airstrip is a location from which aircraft flight operations take place, regardless of whether they involve air cargo, passengers, or neither, and regardless of whether it is for public or private use. Aerodromes in ...

and carried out of drilling in 28 holes during this time. Newhawk Mines constructed an access road and of

underground development Underground Development, Ltd. (formerly Z-Axis, Ltd.) was an American video game developer based in Foster City, California. It was founded in 1994 by David Luntz and sold to Activision in May 2002. Following a rebranding to Underground Develop ...

on the Hawk vein. Further geochemical and geological surveying was performed by Moongold Resources from 1987 to 1989. Mineral exploration conducted by Columbia Gold Mines from 1990 to 1992 consisted of rock sampling, trenching and of drilling in 50 holes.

Protected areas

Mount Edziza and the surrounding area was designated as a

in 1972 to showcase the volcanic landscape; a

recreation area A recreation area is a type of protected area designated in some jurisdictions. By country Canada In the province of British Columbia, recreation areas are lands set aside for recreational use. These lands are also being evaluated to determine w ...

surrounding the park was also established in 1972. In 1989, Mount Edziza Provincial Park roughly doubled in size when was annexed from the

Mount Edziza Recreation Area The Mount Edziza Recreation Area was a recreation area in Cassiar Land District of northwestern British Columbia, Canada, located southeast of the community of Telegraph Creek. It was established on 27 February 1972 along with Mount Edziza Prov ...

. With this annexation, the recreation area was greatly reduced in size to around . This remnant of the recreation area was east of Mount Edziza until 2003 when it was disestablished. Mount Edziza Provincial Park now covers an area of , making it one of the largest provincial parks in British Columbia. In 2021, an approximately

conservation area Protected areas or conservation areas are locations which receive protection because of their recognized natural or cultural values. Protected areas are those areas in which human presence or the exploitation of natural resources (e.g. firewoo ...

called the

Mount Edziza Conservancy Mount is often used as part of the name of specific mountains, e.g. Mount Everest. Mount or Mounts may also refer to: Places * Mount, Cornwall, a village in Warleggan parish, England * Mount, Perranzabuloe, a hamlet in Perranzabuloe parish, C ...

was established east of Mount Edziza along the eastern border of Mount Edziza Provincial Park. It was established in collaboration with Skeena Resources,

, the Tahltan Central Government and the

Nature Conservancy of Canada The Nature Conservancy of Canada (NCC) is a private, non-profit, charitable nature conservation and restoration organisation based in Canada. Since its founding in 1962, the organisation and its partners have protected of land and water acro ...

after Skeena Resources returned their mineral tenures on the Spectrum property. The name of this conservation area was changed to the Tenh Dẕetle Conservancy in 2022 to better reflect the culture, history and tradition of the

Tahltan First Nation The Tahltan First Nation, also known as the Tahltan Indian Band, is a band government of the Tahltan people. Their main community and reserves are located at Telegraph Creek, British Columbia. Their language is the Tahltan language, which is an ...

Accessibility

Mount Edziza lies in a remote location that is accessible only during summer and early autumn. There is no established road access to the mountain, although the

Stewart–Cassiar Highway The Stewart–Cassiar Highway, also known as the Dease Lake Highway and the Stikine Highway, as well as the Kitimat Highway from Kitimat to Terrace, is the northwestern-most highway in the Canadian province of British Columbia. A scenic route th ...

to the east and the Telegraph Creek Road to the northwest both extend within of Mount Edziza. Extending from these roads are

s that provide access to the mountain. From Telegraph Creek, the Buckley Lake Trail extends about southeast along Mess Creek and Three Mile Lake. It then traverses about northeast along Dagaichess Creek and Stinking Lake to the northeastern end of Buckley Lake where it meets with the Klastline River Trail and the Buckley Lake to Mowdade Lake Route. Mount Edziza from Mount Glenora

To the east, the roughly long Klastline River Trail begins at the community of

on the Stewart–Cassiar Highway. It extends northwest and west along the Klastline River for much of its length. The trail enters Mount Edziza Provincial Park at about where Kakiddi Creek drains into the Klastline River. After entering Mount Edziza Provincial Park, the Klastline River Trail traverses northwest along the Klastline River for about and then crosses the river north of Mount Edziza. From there, the Klastline River Trail traverses west for about to the northeastern end of Buckley Lake where it meets with the Buckley Lake Trail and the Buckley Lake to Mowdade Lake Route. The Buckley Lake to Mowdade Lake Route traverses south from Buckley Lake along Buckley Creek and gradually climbs onto the northern end of the Big Raven Plateau where Eve Cone, Sidas Cone and Tsekone Ridge are visible along the route. Most of the Buckley Lake to Mowdade Lake Route is marked by a series of rock

cairn A cairn is a human-made pile (or stack) of stones raised for a purpose, usually as a marker or as a burial mound. The word ''cairn'' comes from the (plural ). Cairns have been and are used for a broad variety of purposes. In prehistory, t ...

s from Tsekone Ridge onwards. The distance between Buckley Lake and Mowdade Lake is about , but the hiking length between these two lakes varies depending on the route taken; it can take a minimum of 7 days to hike the Buckley Lake to Mowdade Lake Route. The weather can change extremely fast along this hiking trail. Mount Edziza can also be accessed by float plane or helicopter, both of which are available for charter at the communities of Iskut and Dease Lake. Kakiddi Lake, Nuttlude Lake, Mowdade Lake, Mowchilla Lake and Buckley Lake are large enough to be used by float-equipped aircraft. Landing on the latter two lakes with a private aircraft requires a letter of authorization from the BC Parks Stikine Senior Park Ranger.

Notes

References

Sources

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

External links

* * * * * {{DEFAULTSORT:Edziza Two-thousanders of British Columbia Pleistocene stratovolcanoes Holocene stratovolcanoes Central volcanoes Tahltan place names

Name and etymology

Geography and geomorphology

Location and climate

Glaciation

Structure

Subfeatures

Drainage

Geology

Background

Composition

Stratigraphy

Pyramid Formation

Ice Peak Formation

Pillow Ridge Formation

Edziza Formation

Kakiddi Formation

Big Raven Formation

Basement

Hazards and monitoring

Human history

Indigenous peoples

Mineral exploration

Protected areas

Accessibility

See also

Notes

References

Sources

External links