Résumés
Abstract
A depositional framework for late Pleistocene sediments in central British Columbia was developed from the composite stratigraphy of glacial sediments found in the Bulkley River region. Nonglacial deposits correlated to the Olympia Nonglacial Interval, are overlain in succession by sub-till, ice-advance sediments, Late Wisconsinan (Fraser Glaciation) till, and late-glacial sediments. Due to local erosion and depositional variability, some of the units are not continuous throughout the region and differ locally in their thickness and complexity. At the onset of the Fraser Glaciation, ice advance was marked by rising base levels in rivers, lake ponding, and ice marginal subaqueous deposition. Physiography and glacier dynamics influenced the position of drainage outlets, direction of water flow, and ponding. The region was completely ice covered during this glaciation and ice-flow directions were variable, being dominantly influenced by the migrating position of ice divides. Deglaciation was marked by the widespread deposition of fine-grained sediments in proglacial lakes and glaciofluvial sands and gravels at locations with unrestricted drainage.
Résumé
Un scénario de sédimentation datant du Pléistocène tardif est élaboré à partir de la stratigraphie glaciaire observée dans la région de la rivière Bulkley. Les dépôts non-glaciaires attribués à l’interstade d’Olympia sont surmontés d’un till d’une avancée glaciaire, d’un till datant du Wisconsinien supérieur (glaciation du Fraser) et de sédiments tardiglaciaires. Plusieurs unités ne sont pas continues dans la région et diffèrent par leur épaisseur et leur complexité, en raison de l’érosion locale et des taux de sédimentation variables. Au début de la glaciation du Fraser, l’avancée des glaces fut accompagnée d’une augmentation du niveau de base des rivières, la création d’étangs et d’une sédimentation près des marges glaciaires. La physiographie et la dynamique glaciaire influence l’emplacement des exutoires de drainage, la direction de l’écoulement des eaux et la création des bassins. La région fut alors entièrement couverte de glace et les directions d’écoulement glaciaire, très variables, furent fortement contrôlées par la migration des lignes de partage glaciaires. La déglaciation se caractérise par la sédimentation de sédiments fins dans les lacs proglaciaires, et des sables et des graviers fluvioglaciaires dans les zones de drainage libres.
Parties annexes
References
- Armstrong, J.E., Crandell, E.R., Easterbrook, D.J. and Noble, J.B., 1965. Late Pleistocene stratigraphy and chronology in southwestern British Columbia and northwestern Washington. Geological Society of America Bulletin, 76 : 321‑330.
- Barrie, J.V., and Conway, K.M., 1999. Late Quaternary glaciation and postglacial stratigraphy of the Northern Pacific margin of Canada. Quaternary Research, 51 : 113‑123.
- Benn, D.I., 1992. The genesis and significance of “hummocky moraine”; evidence from the Isle of Skye. Quaternary Science Reviews, 11 : 781‑799.
- Benn, D.I. and Evans, D.J.A., 1996. The interpretation and classification of subglacially-deformed materials. Quaternary Science Reviews, 15 : 23‑52.
- Bennett, M.R., Huddart, D. and Thomas, G.S.P., 2002. Facies architecture within a regional glaciolacustrine basin: Copper River, Alaska. Quaternary Science Reviews, 21 : 2237‑2279.
- Blaise, B., Clague, J.J. and Mathewes, R.W., 1990. Time of maximum Late Wisconsin Glaciation, west coast of Canada. Quaternary Research, 34 : 282‑295.
- British Columbia Ministry of Forests, 1993. Morice Forest Service Road slide at km 25.2. British Columbia Ministry of Forests (Unpublished Report).
- British Columbia Ministry of Forests, 1996. Slide monitoring at km 17.5. Morice Forest Service Road. British Columbia Ministry of Forests, File J‑856 (Unpublished Report).
- British Columbia Ministry of Transportation and Highways, 1991. Morice River Forest Service Road km 25 slide. British Columbia Ministry of Transportation and Highways (Unpublished Report).
- Broster, B.E. and Clague, J.J., 1987. Advance and retreat glacigenic deformation at Williams Lake, British Columbia. Canadian Journal of Earth Sciences, 24 : 1421‑1430.
- Broster, B.E. and Hicock, S.R., 1985. Multiple flow and support mechanisms and the development of inverse grading in a subaquatic glacigenic debris flow. Sedimentology, 25 : 645‑657.
- Church, B.N. and Barakso, J.J., 1990. Geology, lithogeochemistry and mineralization in the Buck Creek area, British Columbia. British Columbia Geological Survey Branch, Victoria, Paper 1990‑2, 95 p.
- Clague, J.J., 1981. Late Quaternary geology and geochronology of British Columbia, Part 2: Summary and Discussion of Radiocarbon-dated Quaternary History. Geological Survey of Canada, Ottawa, Paper 80‑35, 41 p.
- Clague, J.J., 1984. Quaternary geology and geomorphology, Smithers-Terrace-Prince Rupert area, British Columbia. Geological Survey of Canada, Ottawa, Memoir 413, 71 p. (Includes map 1557A, scale 1:100 000).
- Clague, J.J., 1987. Quaternary stratigraphy and history, Williams Lake, British Columbia. Canadian Journal of Earth Sciences, 24 : 147‑158.
- Clague, J.J., 2000. Recognizing order in chaotic sequences of Quaternary sediments in the Canadian Cordillera. Quaternary International, 68‑71 : 29‑38.
- Donnelly, R. and Harris, C., 1989. Sedimentology and origin of deposits from a small ice-dammed lake, Leirbreen, Norway. Sedimentology, 36 : 581‑600.
- Eyles, N., 1987. Late Pleistocene debris-flow deposits in large glacial lakes in British Columbia and Alaska. Sedimentary Geology, 53 : 33‑71.
- Eyles, N., and Clague, J.J., 1991. Glaciolacustrine sedimentation during advance and retreat of the Cordilleran Ice Sheet in central British Columbia. Géographie physique et Quaternaire, 45 : 317‑331.
- Farstad, L., and Laird, D.G., 1954. Soil survey of the Quesnel, Nechako, François Lake and Bulkley-Terrace areas in the central interior of British Columbia. British Columbia Soil Survey, Victoria, Report No. 4, 88 p.
- Fulton, R.J., 1967. Deglaciation studies in Kamloops region, an area of moderate relief, British Columbia. Geological Survey of Canada, Ottawa, Bulletin 154, 36 p.
- Fulton, R.J., 1975. Quaternary geology and geomorphology, Nicola-Vernon area, British Columbia. Geological Survey of Canada, Ottawa, Memoir 380, 50 p.
- Fulton, R.J., 1991. A conceptual model for growth and decay of the Cordilleran Ice Sheet. Géographie physique et Quaternaire, 45 : 281‑286.
- Ghibaudo, G., 1992. Subaqueous sediment gravity flow deposits: Practical criteria for their field description and classification. Sedimentology, 39 : 423‑454.
- Hambrey, M.J., 1994. Glacial Environments. University of British Columbia Press, Vancouver, British Columbia, 304 p.
- Harington, C.R., Tipper, H.W. and Mott, J.R., 1974. Mammoth from Babine Lake, British Columbia. Canadian Journal of Earth Sciences, 11 : 285‑303.
- Harington, C.R., Plouffe, A. and Jetté, H., 1996. A partial bison (Bison cf. B. latifrons) skeleton from Chuchi Lake, and its implications for the middle Wisconsinan environment of central British Columbia. Géographie physique et Quaternaire, 50 : 73‑80.
- Hart, J.K., 1995. Subglacial erosion, deposition and deformation associated with deformable beds. Progress in Physical Geography, 19 : 173‑191.
- Holland, S.S., 1976. Landforms of British Columbia: a physiographic outline. British Columbia Department of Mines and Petroleum Resources, Victoria, Bulletin No. 48, 138 p.
- Huntley, D.H., and Broster, B.E., 1994. Glacial Lake Camelsfoot; a Late Wisconsinan advance stage proglacial lake in the Fraser River valley, Gang Ranch area, British Columbia. Canadian Journal of Earth Sciences, 31 : 798‑807.
- Levson, V.M., 2001. Quaternary geology of the Babine Porphyry Copper District: Implications for geochemical exploration. Canadian Journal of Earth Sciences, 38 : 737‑749.
- Levson, V.M., Stumpf, A.J., Meldrum, D.G., O’Brien, E.K. and Broster, B.E., 1997. Quaternary geology and ice flow history of the Babine Copper Porphyry Belt, British Columbia, p. 427‑438. In D.V. Lefebvre, W.J. McMillan, and J.G. McArthur, eds., Geological Fieldwork 1996. British Columbia Geological Survey Branch, Victoria, Paper 1997‑1, 480 p.
- Levson, V.M., Stumpf, A.J. and Stuart, A.J., 1998. Quaternary geology and ice-flow studies in the Smithers and Hazelton map areas: Implications for exploration, p. 5.1‑5.8. In Geological Fieldwork 1997. British Columbia Geological Survey Branch, Victoria, Paper 1998‑1, 491 p.
- Levy, L.B., and Jull, A.J.T., 1998. Interpreting the carbonate concretions of Glacial Lake Hitchcock, p. 331. In Abstracts with Programs. Geological Society of America, 1998 Annual Meeting, Toronto, Ontario, Canada, October 26‑29, 1998, 432 p.
- Mate, D.J. and Levson, V.M., 2001. Quaternary stratigraphy and history of the Ootsa Lake-Cheslatta area, Nechako Plateau, central British Columbia. Canadian Journal of Earth Sciences, 38 : 751‑765.
- Mathews, W.H., 1944. Glacial lakes and ice retreat in south-central British Columbia. Royal Society of Canada Transactions, Series 3, 38 : 39‑57.
- Menzies J., 1995. Modern Glacial Environments: Processes, Dynamics and Sediments. Butterworth-Heinemann, Oxford, 621 p.
- Plouffe, A., 1996. Surficial geology of the Cunningham Lake (93K/NW). Geological Survey of Canada, Ottawa, Open File Report 3183, scale 1:100 000.
- Plouffe, A., 1997a. Ice flow and late glacial lakes of the Fraser Glaciation, central British Columbia, p. 133‑143. Geological Survey of Canada, Ottawa, Current Research 1997‑A, 199 p.
- Plouffe, A., 1997b. Géologie glaciaire et étude du contenu de mercure dans le till, partie centrale de la Colombie-Britannique. Thèse de doctorat non publiée, Université de Montréal, 238 p.
- Plouffe, A., 2000. Quaternary geology of the Fort Fraser and Manson River map areas, central British Columbia. Geological Survey of Canada, Ottawa, Bulletin 554, 62 p.
- Plouffe, A., and Jetté, H., 1997. Middle Wisconsinan sediments and paleoecology of central British Columbia: sites at Necoslie and Nautley rivers. Canadian Journal of Earth Sciences, 34 : 200‑208.
- Plouffe, A., and Levson, V.M., 2001. Late Quaternary glacial and interglacial environments of the Nechako River-Cheslatta Lake area, central British Columbia. Canadian Journal of Earth Sciences, 38 : 719‑733.
- Postma, G., 1990. Depositional architecture and facies of river and fan deltas: a synthesis, p. 13‑27. In A. Colella and D.B. Prior, eds., Coarse-grained Deltas. International Association of Sedimentologists, Special Publication 10. Blackwell, Oxford, 357 p.
- Runka, G.G., 1972. Soil resources of the Smithers-Hazelton area. British Columbia Department of Agriculture, Soil Survey Division, Kelowna, British Columbia, 234 p.
- Ryder, J.M., and Clague, J.J., 1989. British Columbia (Quaternary stratigraphy and history), p. 48‑58. In R.J. Fulton, ed., Quaternary Geology of the Canadian Cordillera, Quaternary Geology of Canada and Greenland. Geological Survey of Canada, Ottawa, Geology of Canada, Volume 1, 839 p.
- Ryder, J.M., Fulton, R.J. and Clague, J.J., 1991. The Cordilleran Ice Sheet and the glacial geomorphology of southern and central British Columbia. Géographie physique et Quaternaire, 45 : 365‑377.
- Shaw, J., and Archer, J., 1978. Winter turbidity current deposits in Late Pleistocene glaciolacustrine varves, Okanagan valley, British Columbia, Canada. Boreas, 7 : 123‑130.
- Smith, N.D., and Ashley, G.M., 1985. Proglacial lacustrine environment, p. 135‑216. In G.M. Ashley, J. Shaw and N.D. Smith, eds., Glacial Sedimentary Environments. Society of Economic Paleontologists and Mineralogists, Short Course 16, 246 p.
- Soil Survey Staff, 1994. Keys to Soil Taxonomy, 6th ed., U.S. Department of Agriculture, Soil Conservation Service, Washington DC, 524 p.
- Stumpf, A.J., Broster, B.E. and Levson, V.M., 2000. Multi-phase flow of the Late Wisconsinan Cordilleran Ice Sheet in western Canada. Bulletin of the Geological Society of America, 112 : 1150‑1163.
- Stumpf, A.J., 2001. Late Quaternary ice flow, stratigraphy, and history of the Babine Lake-Bulkley River region, central British Columbia, Canada. Ph.D. thesis, University of New Brunswick, 234 p.
10.7202/032878ar