This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Hodder, K. R. Articles by Gilbert, R. Search for Related Content GeoRef GeoRef Citation Social Bookmarking                         What's this?

Pattern and timing of sediment infill at glacier-fed Mud Lake: implications for lateglacial and Holocene environments in the Monashee Mountain region of British Columbia, Canada

Department of Geography, Queen’s University, Kingston, Ontario K7L 3N6, Canada, kr.hodder{at}utoronto.ca

J. R. Desloges

Department of Geography, University of Toronto, Toronto, Ontario M5S 3G3, Canada

R. Gilbert

Department of Geography, Queen’s University, Kingston, Ontario K7L 3N6, Canada

The Holocene sedimentary infill of proglacial Mud Lake, British Columbia, Canada, was investigated using 3.5 kHz acoustic sub-bottom profiling and sediment samples. The sediment infill is a mixture of silt and clay and is divided into five stratigraphic units: massive silt (Unit 1), weakly laminated silt with very fine sand beds (Unit 2), weakly laminated silt with rippled beds of fine sand (Unit 3), weakly laminated clay with very fine sand laminations (Unit 4) and silt-clay varves (Unit 5). Acoustic reflectors correlate with stratigraphic unit boundaries. Annual accumulation rates were estimated for six age/depth intervals: prior to 9.6 kyr cal. BP, accumulation rates were very high - on the order of several centimetres per year. Early to middle Holocene sediment inputs (9.6-3.6 kyr cal. BP) were variable but low, ranging from 0.3 mm/yr to 1.2 mm/yr. The late Holocene (most recent 3.6 kyr) shows annual accumulation rates that generally exceed 2 mm/yr. Surface sediment reveals a mean of 4.3 mm/yr over the last 20 years. These results are consistent with regional Holocene chronologies and long-term paraglacial succession: (1) maximum sediment and meltwater availability and minimum stabilization by vegetation following Fraser deglaciation replaced by (2) less meltwater and sediment availability during the Hypsithermal, and (3) more stabilized sediment during the early and mid Holocene. Renewal of glacial activity, particularly in the late Neoglacial, has led to increased rates of accumulation in Mud Lake. Despite the contrasting geologic setting of Mud Lake in the Omineca belt, contemporary sediment yield is consistent with the trend of sediment yield with glacier cover in lakes of the adjacent Foreland belt.

Key Words: Glacier-fed lake • acoustic records • sediment yield • varves • Holocene climate • British Columbia • Canada

The Holocene, Vol. 16, No. 5, 705-716 (2006)
DOI: 10.1191/0959683606hl965rp


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?