Mess Creek Escarpment | |
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Coordinates: 57°34′35″N130°47′58″W / 57.57639°N 130.79944°W [1] | |
Location | Cassiar Land District, British Columbia, Canada [2] |
Range | Tahltan Highland [2] |
Part of | East-central side of Mess Creek valley and west-central side of the Mount Edziza complex [2] [3] |
Defining authority | BC Geographic Names office in Victoria, British Columbia [1] [4] |
Elevation | Above 1,700 m (5,500 ft) [2] |
Topo map | NTS 104G10 Mount Edziza [1] |
Designation | Mount Edziza Provincial Park [2] |
Formations | Oldest to youngest: Raspberry Formation, Armadillo Formation, Nido Formation, Spectrum Formation, Ice Peak Formation, Big Raven Formation [5] |
Rocks | Comendite, trachyte, hawaiite, alkali basalt [5] |
Location in Mount Edziza Provincial Park |
The Mess Creek Escarpment is a long, discontinuous cliff along Mess Creek in Cassiar Land District of northwestern British Columbia, Canada. It forms the east-central side of Mess Creek valley and consists of two segments separated about 5 kilometres (3.1 miles) by Walkout Creek valley. The northern segment extends about 8 kilometres (5.0 miles) southeast along the southwestern side of the Big Raven Plateau while the southern segment extends generally south along the northwestern, western and southwestern edges of the Kitsu Plateau for about 10 kilometres (6.2 miles). With an elevation of more than 1,700 metres (5,500 feet), the Mess Creek Escarpment rises more than 910 metres (3,000 feet) above the floor of Mess Creek valley. The escarpment lies within the boundaries of Mount Edziza Provincial Park.
The Mess Creek Escarpment forms the west-central side of the Mount Edziza volcanic complex and consists of at least six geological formations, each being the product of a distinct period of volcanic activity over the last 7.5 million years. With the exception of the Armadillo and Spectrum formations which consist of basalt, trachyte and comendite, volcanic rocks of the Raspberry, Nido, Ice Peak and Big Raven formations exposed along the escarpment are mainly basaltic in composition. Underlying these geological formations are much older Paleozoic–Mesozoic rocks of the Stikinia terrane and Cretaceous–Paleocene rocks of the Sustut Group.
The name of the escarpment was adopted on January 2, 1980, on the National Topographic System map 104G after being submitted to the BC Geographical Names office by the Geological Survey of Canada. [2] It was required for geology reporting purposes since Jack Souther, a volcanologist of the Geological Survey of Canada, was studying the area in detail between 1970 and 1992. [6] [7] [8] The escarpment was named for its association with Mess Creek, a tributary of the Stikine River which flows into Sumner Strait of southeast Alaska. [1] [9] [10] It is one of two officially named escarpments in British Columbia, the other being the Etsho Escarpment northeast of Fort Nelson in Peace River Land District. [11] [12]
The Mess Creek Escarpment is in the Tahltan Highland east of the Boundary Ranges of the Coast Mountains and west of the Skeena Mountains and Klastline Plateau in Cassiar Land District. [2] It forms the east-central side of Mess Creek valley and the west-central side of the Mount Edziza volcanic complex, consisting of two segments separated about 5 kilometres (3.1 miles) by Walkout Creek valley. [2] [3] The northern segment extends southeast along the southwestern side of the Big Raven Plateau for about 8 kilometres (5.0 miles) and reaches an elevation of 1,700 metres (5,500 feet). At least four unnamed streams flow down this segment of the escarpment into Mess Creek which is less than 760 metres (2,500 feet) in elevation. [2]
The southern segment reaches an elevation of more than 1,700 metres (5,500 feet) and extends generally south along the northwestern, western and southwestern edges of the Kitsu Plateau for about 10 kilometres (6.2 miles). [2] [5] The Mess Creek Escarpment therefore has a total length of approximately 23 kilometres (14 miles) and rises more than 910 metres (3,000 feet) above the floor of Mess Creek valley. [2] At least five streams flow down the southern segment into Mess Creek valley, including Kitsu Creek which originates from Kitsu Peak in the Spectrum Range. [2] [13] Mess Lake, an expansion of Mess Creek, lies below the southern segment of the Mess Creek Escarpment. [5] [14]
The Mess Creek Escarpment is subdivided into at least six geological formations, each being the product of a distinct period of volcanic activity. [5] [15] 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. [16] The two oldest geological formations comprising the Mess Creek Escarpment are the Raspberry and Armadillo formations which were deposited by volcanic eruptions during the first magmatic cycle between 7.5 and 6 million years ago. Overlying these two geological formations are the Nido and Spectrum formations which were deposited between 6 and 3 million years ago during the second magmatic cycle. Volcanism during the third magmatic cycle about 1 million years ago created the Ice Peak Formation which overlies the Nido Formation. The fifth oldest geological formation comprising the Mess Creek Escarpment is the Big Raven Formation which was deposited during the fifth magmatic cycle in the last 20,000 years. [5] [15]
The Raspberry Formation consists of flat-lying basaltic lava flows interbedded with scoria and is exposed along the base of the Mess Creek Escarpment where it has an elevation of less than 1,310 metres (4,300 feet). [5] More than 180 metres (590 feet) of Raspberry lava flows are exposed in the Mess Creek Escarpment, most of which were erupted from a shield volcano that formed on a Late Miocene erosion surface. [17] [18] These lava flows travelled westward into the ancestral valley of Mess Creek and originated from vents north of Raspberry Pass which were subsequently buried under younger volcanic deposits. A minimum age for the timing of Raspberry volcanism is 7.4–6.2 million years. [18]
Basaltic lava flows of the 6.3-million-year-old Armadillo Formation are interbedded with air-fall pumice and ash flows of trachytic and comenditic compositions. [18] [19] They were highly fluid and mobile at the time of their eruption as evidenced by their extreme persistence and relatively narrow thicknesses; individual basalt flows are normally less than 3 metres (9.8 feet) thick. The source of these flows was probably a cluster of vents further to the north called Sezill Volcano which may have been active prior to the onset of Armadillo volcanism. [20] In contrast, the air-fall pumice and ash flows probably originated from the more than 4-kilometre-in diameter (2.5-mile) Armadillo Peak caldera east of the Mess Creek Escarpment. [18] [21]
The 4.4-million-year-old Nido Formation consists of two stratigraphic units, both of which are exposed along the Mess Creek Escarpment and overlie the Raspberry and Armadillo formations. [18] [15] Alkali basalt and minor hawaiite of the Tenchen Member are exposed along the northern segment of the escarpment and comprise lava flows, flow breccia and agglutinate; the lava flows are brown-weathered and columnar jointed. [18] [22] The Tenchen Member was erupted from at least three major volcanoes and several smaller satellitic centres which have been either buried under younger volcanic deposits or destroyed by erosion. [22] Alkali basalt and minor hawaiite of the Kounugu Member are exposed along the southern segment of the Mess Creek Escarpment and are in the form of lava flows, flow breccia and agglutinate. [18] The Kounugu Member was erupted from at least four volcanoes which have also been deeply eroded and extensively buried under younger volcanic rocks. [23]
Overlying the Kounugu Member is the 3.1-million-year-old Spectrum Formation which mainly occurs along the southern segment of the Mess Creek Escarpment. [5] [15] This geological formation largely consists of comendite, pantellerite and pantelleritic trachyte which are in the form of lava domes and lava flows, as well as minor breccia and ash flow deposits. [5] Spectrum trachyte flows exposed along the upper part of the Mess Creek Escarpment are relatively thin compared to those forming the Spectrum Range to the southeast, but they are the most distal remnants of the main Spectrum Dome. [5] [24] These trachyte flows are overlain by alkali basalt of the Kitsu Member which is also exposed along the escarpment. [5] This alkali basalt is in the form of lava flows and likely originated from vents of the Spectrum Dome which have since been destroyed by erosion. [25]
The approximately 1-million-year-old Ice Peak Formation mainly occurs along the northern segment of the Mess Creek Escarpment where it overlies the Tenchen Member of the Nido Formation, as well as the older Armadillo and Raspberry formations. [5] [15] Most of the volcanic rocks comprising this geological formation were erupted from Ice Peak on the Big Raven Plateau, but the main Ice Peak Formation rock exposed along the escarpment is basalt from Camp Hill near the southwestern edge of the plateau. [5] [26] This basalt mainly erupted as subaerial lava flows which are exposed along the Mess Creek Escarpment for about 8 kilometres (5.0 miles) and are almost completely buried under colluvium deposits on the Big Raven Plateau. [5] Just southwest of Camp Hill, the basalt is in the form of tuff breccia and pillow lava which are probably the products of quenching in meltwater when Camp Hill initially erupted under glacial ice. [5] [27]
The Big Raven Formation mainly occurs along the southern segment of the Mess Creek Escarpment where it overlies the Nido and Spectrum formations. [5] This geological formation is the youngest and uppermost along the entire Mess Creek Escarpment, consisting of hawaiite and alkali basalt which erupted from three Holocene pyroclastic cones in the Mess Lake Lava Field. Alkali basalt flows from the two oldest cones travelled westward on the Kitsu Plateau to the edge of the escarpment where they cooled into crude columnar joints. [5] [28] These lava flows most likely cascaded over the escarpment into the densely wooded valley of Mess Creek, but no evidence of this phenomenon has been found on or below the escarpment. [28] Overlying these alkali basalt flows and the Spectrum Formation is a 6.5-kilometre-long (4.0-mile) and 2.5-kilometre-wide (1.6-mile) hawaiitic air-fall tephra deposit which also occurs along the edge of the Mess Creek Escarpment. [5] [28] The source of this tephra was The Ash Pit which formed at the southern end of the Mess Creek Escarpment and produced a towering lava fountain. [5] [29]
As a part of the Mount Edziza volcanic complex, the Mess Creek Escarpment is underlain by the Stikinia terrane. [3] [30] This is a Paleozoic and Mesozoic suite of volcanic, sedimentary and metamorphic rocks that accreted to the continental margin of North America during the Jurassic. [5] [30] [31] The rocks of this terrane are largely buried under landslide and colluvium deposits, as well as stream gravel, outwash and braided channel deposits. Minor exposures of Cretaceous–Paleocene sedimentary rocks assigned to the Sustut Group are present in the mouth of Nagha Creek valley at the southern end of the Mess Creek Escarpment and are in the form of conglomerates, sandstones, arkoses, siltstones, shales or minor coal. [5]
The Mess Creek Escarpment lies at the western end of Mount Edziza Provincial Park, a protected area founded in 1972 to showcase the volcanic landscape. [2] [32] This remote wilderness area of northwestern British Columbia is not accessible by motorized vehicles to help protect the very sensitive environment. Instead, access is mainly via aircraft or unmaintained hiking trails that cross creeks. [32] Mount Edziza Provincial Park covers 266,180 hectares (657,700 acres), making it one of the largest provincial parks in British Columbia. [32] [33] Hunting, camping, fishing, hiking, wildlife viewing and nature studying are some of the activities available in Mount Edziza Provincial Park. [32]
Wildlife in the area includes moose, caribou, mountain goats, stone sheep, wolves, bears, squirrels, owls, ptarmigans, ravens, gyrfalcons, grouse and migratory songbirds. The climate is characterized by warm summers and cold, snowy winters; temperatures are warmest in mid-summer during the day when they may hit the 30 degrees Celsius (86 degrees Fahrenheit) range. However, temperatures can drop below freezing during summer nights, making snow or freezing rain a possibility at any time of the year. [32]
From near the Eastman Creek Rest Area south of Kinaskan Lake on the Stewart–Cassiar Highway, the historic Yukon Telegraph Trail extends about 15 kilometres (9.3 miles) west to the Little Iskut River. From there, it enters Mount Edziza Provincial Park and continues another 15 kilometres (9.3 miles) west along Bourgeaux Creek through Raspberry Pass. [34] The telegraph trail then continues to the northwest through Raspberry Creek valley along the northern edge of the Kitsu Plateau for about 15 kilometres (9.3 miles) to Mess Creek valley. [2] [34] Only short segments of the Yukon Telegraph Trail are still passible, having been mostly overgrown since maintenance of the trail ended in 1936. [35]
The Mess Creek Escarpment can be accessed by float plane or helicopter, both of which are available for charter at the communities of Iskut and Dease Lake. [35] Private aircraft are prohibited from landing on the neighbouring Kitsu Plateau lava flows. [2] [32] Mess Lake is large enough to be used by float-equipped aircraft, but landing on it with a private aircraft requires a letter of authorization from the BC Parks Stikine Senior Park Ranger. [32]
Mount Edziza is a volcanic mountain in Cassiar Land District of northwestern British Columbia, Canada. It is located on the Big Raven Plateau of the Tahltan Highland which extends along the western side of the Stikine Plateau. Mount Edziza has an elevation of 2,786 metres, making it the highest point of the Mount Edziza volcanic complex and one of the highest volcanoes in Canada. However, it had an elevation of at least 3,396 metres 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, 2-kilometre-in diameter (1.2-mile) crater. The mountain contains several lava domes, cinder cones and lava fields on its flanks, as well as an ice cap containing several outlet glaciers which extend to lower elevations. All sides of Mount Edziza are drained by tributaries of Mess Creek and Kakiddi Creek which are situated within the Stikine River watershed.
The Spectrum Range, formerly gazetted as the Spectrum Mountains and the Rainbow Mountains, is a small mountain range in Cassiar Land District of northwestern British Columbia, Canada. Located at the southern end of the Tahltan Highland, it borders the Skeena Mountains in the east and the Boundary Ranges of the Coast Mountains in the west. The Spectrum Range is surrounded by the Arctic Lake Plateau in the southwest and the Kitsu Plateau in the northwest, both of which contain volcanic features such as cinder cones. It lies at the southern end of the Mount Edziza volcanic complex which includes the two neighbouring plateaus, as well as Mount Edziza and the Big Raven Plateau to the north. The mountain range is drained on all sides by streams within the Stikine River watershed and, unlike Mount Edziza to the north, contains relatively small separate glaciers. Mount Edziza Provincial Park is the main protected area surrounding the Spectrum Range.
Coffee Crater is a cinder cone in Cassiar Land District of northwestern British Columbia, Canada. It has an elevation of 2,000 metres and is one of several volcanic cones in the Snowshoe Lava Field at the southern end of the Big Raven Plateau. The cone is southeast of the community of Telegraph Creek in Mount Edziza Provincial Park, which is one of the largest provincial parks in British Columbia. The climate in the area is characterized by warm summers and cold, snowy winters. However, temperatures can drop below freezing during summer nights, making snow or freezing rain a possibility at any time of the year.
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, Walkout Creek and the Klastline River. The plateau is drained by many small streams that flow into these neighbouring valleys and, unlike the valleys, it is relatively barren of vegetation. Stream erosion has resulted in the creation of canyons with intervening ridges on the eastern and western sides of the plateau, resulting in the creation of rugged terrain. The plateau is in Mount Edziza Provincial Park which is one of the largest provincial parks in British Columbia. Access to the Big Raven Plateau is mainly by aircraft or by a network of footpaths from surrounding roads.
The Kitsu Plateau is a small 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, Nagha Creek and Raspberry Creek. The plateau is drained by many small streams that flow into these neighbouring valleys and, unlike the valleys, it is relatively barren of vegetation. Surrounding the Kitsu Plateau is Mount Edziza Provincial Park which is one of the largest provincial parks in British Columbia. Access to this remote plateau is mainly by aircraft since motorized vehicles are prohibited from entering Mount Edziza Provincial Park.
Tennena Cone, alternatively Icebridge Cone, is a small volcanic cone in Cassiar Land District of northwestern British Columbia, Canada. It has an elevation of 2,390 metres and lies on the upper western flank of Ice Peak, the prominent south peak of Mount Edziza. The cone is almost completely surrounded by Mount Edziza's ice cap and is one of several volcanoes in the Snowshoe Lava Field on the Big Raven Plateau. Tennena Cone is 200 metres high, 1,200 metres long and up to 600 metres wide, its symmetrical structure resembling a black pyramid. The cone and the surrounding area are in Mount Edziza Provincial Park which also includes the Spectrum Range to the south.
The Mount Edziza volcanic complex is a group of volcanoes and associated lava flows in northwestern British Columbia, Canada. Located on the Tahltan Highland, it is 40 kilometres southeast of Telegraph Creek and 85 kilometres southwest of Dease Lake. The complex encompasses a broad, steep-sided lava plateau that extends over 1,000 square kilometres. Its highest summit is 2,786 metres in elevation, making the MEVC the highest of four large complexes in an extensive north–south trending volcanic region. It is obscured by an ice cap characterized by several outlet glaciers that stretch out to lower altitudes.
Cartoona Ridge is a mountain ridge extending east from the eastern side of the Mount Edziza volcanic complex in northwestern British Columbia, Canada. It is bounded on the north by Shaman Creek valley, on the south by Chakima Creek valley, on the east by Kakiddi Creek valley and on the west by the Big Raven Plateau. Its highest point and only named peak is Cartoona Peak at the westernmost end of the ridge with an elevation of 2,300 metres. Carttona Ridge is one of three ridges east of the Big Raven Plateau named by Canadian volcanologist Jack Souther, the other two being Idiji Ridge and Sorcery Ridge to the north.
The Little Iskut Formation is a stratigraphic unit of Miocene age in northwestern British Columbia, Canada.
The Raspberry Formation is a stratigraphic unit of Miocene age in northwestern British Columbia, Canada.
The Armadillo Formation is a stratigraphic unit of Miocene age in northwestern British Columbia, Canada.
The Nido Formation is a stratigraphic unit of Neogene age in northwestern British Columbia, Canada.
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 six older formations of this volcanic complex. The main volcanic rocks of the Big Raven Formation are alkali basalts and hawaiites, although a small volume of trachyte comprises the Sheep Track Member. These rocks were deposited by volcanic eruptions in the last 20,000 years during the latest magmatic cycle of the MEVC. Alkali basalt and hawaiite are in the form of lava flows and small volcanic cones while trachyte of the Sheep Track Member is mainly in the form of volcanic ejecta which covers an area of about 40 square kilometres.
The Mount Edziza volcanic complex (MEVC) in British Columbia, Canada, has a history of volcanism that spans more than 7 million years. It has taken place during five cycles of magmatic activity, each producing less volcanic material than the previous one. Volcanism during these cycles has created several types of volcanoes, including cinder cones, stratovolcanoes, subglacial volcanoes, shield volcanoes and lava domes. The roughly 1,000-square-kilometre (400-square-mile) volcanic plateau forming the base of the MEVC originated from the successive eruptions of highly mobile lava flows. Volcanic rocks such as basalt, trachybasalt, benmoreite, tristanite, mugearite, trachyte and rhyolite were deposited by multiple eruptions of the MEVC; the latter six rock types are products of varying degrees of magmatic differentiation in underground magma reservoirs. Renewed effusive volcanism could block local streams with lava flows whereas renewed explosive volcanism could disrupt air traffic with volcanic ash across parts of northwestern Canada. At least 10 distinct flows of obsidian were produced by volcanism of the MEVC, some of which were exploited by indigenous peoples in prehistoric times to make tools and weaponry.
Gnu Butte is a butte in Cassiar Land District of northwestern British Columbia, Canada. It is located southeast of Telegraph Creek on the northwestern side of Raspberry Pass. The western and southern sides of the butte are surrounded by Raspberry Creek while the eastern and northern sides of the butte are surrounded by Flyin Creek. Gnu Butte lies on the Tahltan Highland between Mess Lake and Mowdade Lake in Mount Edziza Provincial Park. It bears a resemblance to flat-topped hills in parts of Africa, hence its name.
The Edziza Formation is a stratigraphic unit of Pleistocene age in northwestern British Columbia, Canada. First described in 1984, the Edziza Formation was mapped as one of several geological formations of the Mount Edziza volcanic complex. It overlies at least four other geological formations of this volcanic complex that differ in age and composition. The main volcanic rock comprising the Edziza Formation is trachyte which was deposited by volcanic eruptions at the end of the third magmatic cycle of the Mount Edziza volcanic complex 0.9 million years ago.
Artifact Ridge is a mountain ridge extending southeast from the eastern side of the Mount Edziza volcanic complex in northwestern British Columbia, Canada. It is bounded on the north by Bourgeaux Creek valley, on the south by Artifact Creek valley, on the east by the Little Iskut River valley and on the west by the Kitsu Plateau. The ridge is at the southeastern end of Mount Edziza Provincial Park and gets its name from the knapping of obsidian tools and points by early Tahltan hunters. Destell Pass cuts north–south through the westernmost end of Artifact Ridge.
Yagi Ridge is a mountain ridge extending northwest from the middle of the Spectrum Range at the southern end of the Mount Edziza volcanic complex in northwestern British Columbia, Canada. It is bounded on the north by Nagha Glacier and Nagha Creek valley, on the south by Yeda Creek on the Arctic Lake Plateau and on the west by Mess Creek valley. Yagi Ridge reaches an elevation of 2,243 metres at the head of Nagha Glacier where its eastern end adjoins to the Spectrum Range just northwest of Yeda Peak.
Idiji 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 south by a valley containing an unnamed creek, on the east by Tennaya Creek valley and on the north by cirques extending east of Ice Peak. Idiji Ridge takes its name from the adjacent Idiji Glacier; Idiji means "it thunders" in the Tahltan language.
Kitsu Peak is the highest summit of the Spectrum Range at the southern end of the Mount Edziza volcanic complex in northwestern British Columbia, Canada. It is bounded on the west by Nagha Creek valley, on the northwest by the Kitsu Plateau, on the northeast by Obsidian Ridge, on the east by Stewbomb Creek valley and on the southwest by Nagha Glacier and Yagi Ridge. It has an elevation of 2,430 metres and lies at the northern end of the Spectrum Range.