| Tennena Cone | |
|---|---|
 Tennena Cone from the northwest | |
| Highest point | |
| Elevation | 2,390 m (7,840 ft)[1] |
| Coordinates | 57°41′03″N 130°39′44″W / 57.68417°N 130.66222°W[2] |
| Dimensions | |
| Length | 1.200 km (0.746 mi)[1] |
| Width | 0.6 km (0.37 mi)[1] |
| Geography | |
  Tennena Cone Location in British Columbia | |
| Country | Canada[3] |
| Province | British Columbia[3] |
| District | Cassiar Land District[2] |
| Protected area | Mount Edziza Provincial Park[2] |
| Topo map | NTS 104G10 Mount Edziza[2] |
| Geology | |
| Formed by | Subglacial mound[4] |
| Type of rock | Alkali basalt[5] |
| Volcanic region | Northern Cordilleran Province[6] |
| Last eruption | Pleistocene or Holocene[4][7] |
Tennena Cone is a small volcanic cone in Cassiar Land District of northwestern British Columbia, Canada.
Name and etymology
editThe name of the volcanic cone was officially adopted on January 2, 1980, 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.[2][8][9] Tennena is a combination of the Tahltan words ten and nena, which mean ice and bridge respectively.[5] It was chosen because Tennena Cone is almost completely surrounded by glacial ice in an alpine environment.[2][5] Tennena Cone and the associated volcanic rocks have been called the Tennena volcanic centre.[3]
Geography
editTennena Cone is in Cassiar Land District of northwestern British Columbia and resembles a symmetrical, 200-metre-high (660-foot), 1,200-metre-long (3,900-foot) and up to 600-metre-wide (2,000-foot) black pyramid.[2][7][10] Its northern, eastern and southern flanks are mantled by the roughly 70-square-kilometre (27-square-mile) Mount Edziza ice cap and rises about 150 metres (490 feet) above the ice surface.[5][11] Tennena Cone reaches an elevation of 2,390 metres (7,840 feet) on the upper western flank of Ice Peak and lies at the northern end of Tencho Glacier, the largest glacier of the Mount Edziza volcanic complex.[1][5][12]
At lower elevations, Tennena Cone is surrounded by Ornostay Bluff in the northwest and by Kopsick Bluff in the southwest.[5] Between these two bluffs is the head of Sezill Creek which flows northwest from the surrounding Big Raven Plateau and then drains into Taweh Creek, a tributary of Mess Creek.[5][13][14] The Big Raven Plateau is the northernmost subdivision of the Mount Edziza volcanic complex which comprises a broad intermontane plateau that has been volcanically active periodically for the last 7.5 million years.[15]
Tennena Cone lies in Mount Edziza Provincial Park southeast of the community of Telegraph Creek.[2] With an area of 266,180 hectares (657,700 acres), Mount Edziza Provincial Park is one of the largest provincial parks in British Columbia and was established in 1972 to preserve the volcanic landscape.[16][17] It includes not only the Mount Edziza area but also the Spectrum Range to the south from which it is separated by Raspberry Pass.[17]
Geology
editLithology
editTennena Cone consists mainly of Big Raven Formation alkali basalt that comprises four mappable subdivisions, all of which are exposed on the eastern, southern and western flanks of the cone.[5][18] The first subdivision is massive and crudely bedded tuff breccia exposed in near vertical cliffs on the flanks of Tennena Cone. Exposed in scarps on the eastern and southern flanks of Tennena Cone is lapilli tuff of the second subdivision which forms 10-to-30-centimetre-thick (3.9-to-11.8-inch) beds.[19] Two 1-metre-wide (3.3-foot) dikes comprise the third subdivision, both of which consist of fragmented plagioclase-phyric rock.[19] The first dike forms a 5-metre-high (16-foot) remnant and is exposed on the eastern flank of Tennena Cone while the second dike is exposed 50 metres (160 feet) to the south. In addition to occuring on the eastern flank, the second dike is also exposed on the western flank and along the summit ridge of Tennena Cone.[20]
Formation
editThe precise age of Tennena Cone is unknown but it may have formed during the Last Glacial Maximum when the Mount Edziza volcanic complex was covered by the Cordilleran Ice Sheet.[3] Another possibility is that Tennena Cone formed during a Younger Dryas expansion of the still-extant Mount Edziza ice cap or during the height of the neoglaciation when the ice cap was much larger in area than it is now.[3][21] Argon–argon dating of glassy pillows from Tennena Cone has yielded ages of 0.011 ± 0.033 million years and 0.005 ± 0.033 million years.[22]
Significance
editSee also
editReferences
edit- ^ a b c d Hungerford et al. 2014, p. 41.
- ^ a b c d e f g h i "Tennena Cone". BC Geographical Names. Archived from the original on 2024-06-08. Retrieved 2024-07-03.
- ^ a b c d e Hungerford et al. 2014, p. 39.
- ^ a b "Tennena Cone". Catalogue of Canadian volcanoes. Natural Resources Canada. 2009-03-10. Archived from the original on 2010-12-11. Retrieved 2024-07-03.
- ^ a b c d e f g h Souther, J. G. (1988). "1623A" (Geologic map). Geology, Mount Edziza Volcanic Complex, British Columbia. 1:50,000. Geological Survey of Canada. doi:10.4095/133498.
- ^ Hungerford et al. 2014, pp. 39, 40.
- ^ a b Hungerford et al. 2014, pp. 39, 41.
- ^ "Acceptance of the 1995 Career Achievement Award by Jack Souther" (PDF). Ash Fall. Geological Association of Canada. 1996. p. 3. Archived from the original (PDF) on 2018-12-05.
- ^ "Stikine volcanic belt: Mount Edziza". Catalogue of Canadian volcanoes. Natural Resources Canada. 2009-04-01. Archived from the original on 2009-06-08. Retrieved 2024-07-03.
- ^ Souther 1992, p. 230.
- ^ Field, William O. (1975). "Coast Mountains: Boundary Ranges (Alaska, British Columbia, and Yukon Territory)". Mountain Glaciers of the Northern Hemisphere. Vol. 2. Cold Regions Research and Engineering Laboratory. p. 43. Retrieved 2024-06-19.
- ^ Souther 1992, pp. 26, 320.
- ^ "Sezill Creek". BC Geographical Names. Archived from the original on 2021-10-01. Retrieved 2024-07-03.
- ^ "Taweh Creek". BC Geographical Names. Archived from the original on 2021-10-01. Retrieved 2024-07-03.
- ^ Wood, Charles A.; Kienle, Jürgen (1990). Volcanoes of North America: United States and Canada. Cambridge University Press. pp. 124, 125. ISBN 0-521-43811-X.
- ^ "Edziza: Photo Gallery". Global Volcanism Program. Smithsonian Institution. Archived from the original on 2021-09-21. Retrieved 2024-07-04.
- ^ a b "Mount Edziza Provincial Park". BC Parks. Archived from the original on 2023-01-23. Retrieved 2024-07-03.
- ^ Hungerford et al. 2014, p. 46.
- ^ a b Hungerford et al. 2014, pp. 41, 46.
- ^ Hungerford et al. 2014, pp. 43.
- ^ Souther 1992, p. 26.
- ^ Hungerford et al. 2014, p. 52.
Sources
edit- Hungerford, Jefferson D. G.; Edwards, Benjamin R.; Skilling, Ian P.; Cameron, Barry I. (2014). "Evolution of a subglacial basaltic lava flow field: Tennena volcanic center, Mount Edziza volcanic complex, British Columbia, Canada". Journal of Volcanology and Geothermal Research. 272. Elsevier: 39–58. doi:10.1016/j.jvolgeores.2013.09.012. ISSN 0377-0273.
- Souther, J. G. (1992). The Late Cenozoic Mount Edziza Volcanic Complex, British Columbia. Geological Survey of Canada. doi:10.4095/133497. ISBN 0-660-14407-7.
