Flood-Induced Turbidites From Northern Hudson Bay And Western Hudson Strait: A Two-Pulse Record Of Lake Agassiz Final Outburst Flood?
In Hudson Bay and Hudson Strait, the rapid collapse of the Laurentide Ice Sheet (LIS) culminated in the catastrophic drainage of proglacial Lake Agassiz into the North Atlantic around 8500 cal BP. It has been suggested that this catastrophic event may have triggered the 8200 cal BP cold event recorded in Greenland ice cores. Evidence for that outburst flood was the identification of a centimeter to decimeter-thick hematiterich red layer that was observed in Hudson Strait sediments around 8000 yr BP. In this paper, we have identified a sequence of two flood-induced turbidites (i.e., hyperpycnites) in a reddish layer from two cores collected in northern Hudson Bay (core AMD0509-27bLEH) and western Hudson Strait (core AMD0509-28PC) in 2005 onboard the ice-breaker CCGS Amundsen. These two reddish layers can be correlated to a red bed previously identified as a regional isochron in Hudson Strait and associated with the final drainage of Lake Agassiz around 8500 cal BP. Regardless of the exact timing of the catastrophic drainage, the hyperpycnites described in this paper suggest that they were deposited following two pulses, which is in agreement with the one of the scenarios proposed by Clarke et al. (2003) [Science 301, 922-923] for the drainage of Lake Agassiz. Finally, this study demonstrates for the first time the turbiditic and the flood-induced nature of the Hudson Strait red bed isochron.
KeywordsPetroleum Sedimentation Stratification Silt Turbidity
Unable to display preview. Download preview PDF.
- Andrews, J.T., Maclean, B., Kerwin, M., Manley, W., Jennings, A.E., Hall, F., 1995. Final stages in the collapse of the Laurentide Ice Sheet, Hudson Strait, Canada, NWT: 14C AMS dates, seismics stratigraphy, and magnetic susceptibility logs. Quaternary Science Reviews 14, 983–1004.CrossRefGoogle Scholar
- Chapron, E., Juvigné, E., Mulsow, S., Ariztegui, D., Magand, O., Bertrand, S., Pino, M., Chapron, O., subm. Clastic sedimentation processes in Lago Puyehue: Implications for natural hazards and paleoenvironment reconstructions in the Chilean Lake District, 40.5oS. Sedimentary Geology.Google Scholar
- Clarke, G.K., Seidov, D., Haupt, B.J., 2004a. Freshwater ocean forcing scenarios for the megaflood from glacial Lake Agassiz. Eos Trans. AGU, 85 (17), Jt. Assem. Suppl., Abstract GC12A-02.Google Scholar
- Guyard, H., St-Onge, G., Chapron, E., Anselmetti, F., Francus, P., 2007. The AD 1881 earthquake-triggered slump and late Hocoloce exceptional flood-induced turbidites from proglacial Lake Bramant, Western French Alps. See this book.Google Scholar
- Hall, F.R., Andrews, J.T., Kerwin, M., Smith, L.M., 2001. Studies of sediment colour, whole-core magnetic susceptibility, and sediment magnetism of Hudson Strait-Labrador Shelf region: CSS Hudson cruises 90023 and 93034. In B. MacLean (Ed.), Late Quaternary sediments, depositional environments, and Late Glacial/Deglacial history derived from marine and terrestrial studies. Geological Survey of Canada Bulletin 566, pp. 161-170.Google Scholar
- Kneller, B.C., 1995. Beyond the turbidite paradigm: Physical models for deposition of turbidites and their implications for reservoir prediction. In Hartley, A.J., Prosser, D.J. (Eds.), Characterization of deep marine clastic systems. Geological Society [London] Special Publication 94, pp. 31–49.Google Scholar
- Mulder, T., Syvitski, J.P.M., 1995. Turbidity currents generated at river mouths during exceptional discharges to the world oceans. Journal of Geology 103,285–299.Google Scholar
- Mulder, T., Syvitski, J.P.M., Migeon, S., Faugères, J-C., Savoye, B., 2003. Marine hyperpycnal flows:initiation, behavior and related deposits A review Marine and Petroleum. Geology 20, 861–882.Google Scholar
- Shilts, W.W., 1986. Glaciation of the Hudson Bay region. In I.P. Martini, (Ed.), Canadian Inland Seas. Elsevier Oceanography Series 44, Elsevier, New York, pp. 55–78.Google Scholar
- St-Onge, G., Mulder, T., Francus, P., Long., B. 2007. Continuous physical properties of cored marine sediments. In C. Hillaire-Marcel and A. de Vernal (Eds.), Proxies in Late Cenozoic Paleoceanography, Elsevier, pp. 65-101.Google Scholar