CGRG Bibliography of Canadian Geomorphology
Search Results
Author : Grubb, M.
Date : 2009.
Title : Kitsumkalum Lake: A history of sedimentary variance .
Publication : 51st Annual Meeting of the Western Division, Canadian Association of Geographers. March 5-7, 2009. Vancouver Island University, Nanaimo, British Columbia.
Issue :
Page(s) :
Abstract
Varved lake sediments offer valuable records of environmental change when combined witli instrumental records, historical documents, aerial photography, and radiometric dating. We analyzed inorganic varved lake sediments from proglacial Kitsumkalum Lake and discovered recent and historic changes in sedimentation. Inter-annual variations in varve thickness can be attributed to large episodic hydro-climatic events in the region. The decrease in varve thickness over time is most likely attributed to a decrease in glacier cover and watershed sediment storage. An abrupt facies change present in the bottom of three sediment cores from the distal end of Kitsumkalum Lake delineates a dramatic change in sedimentation from sandy laminations to silt and clay couplets. Hemlock (Tsuga heterophylla) needles at the boundary between facies were radiocarbon dated and show that the sedimentation change occurred 325 ± 15 14C yr BP (381 ± 25 cal yr BP). The cause of the abrupt change in sediment size may be attributed to the progradation of the Nelson River delta further into proglacial Kitsumkalum Lake. Multiple working hypotheses will be discussed further.
Bibliography of Canadian Geomorphology