CGRG Bibliography of Canadian Geomorphology
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Author : Davidge, G. D
Date : 1994
Title : Physical limnology and sedimentology of Romulus Lake: a meromictic lake in the Canadian High Arctic
Publication : M.Sc. thesis, Department of Geography, Queen's University. Kingston
Issue :
Page(s) : 114 pp
Abstract
Modern lake sediments may be divided into sediments deposited above the chemocline and those deposited in the stagnant water below the chemocline. Sediments below the chemocline reveal thin (0.5-1 mm) laminae of alternating olive brown and black material, reflecting textural differences between the coarser, lighter coloured silts and fine sands and the darker very fine sediments. The sedimentary environment is dominated by suspension settling of clastic material, controlled primarily by sediment inputs during the snow and ice melt period.210Pb dating of these sediments suggest that sedimentation rates are typical for the region (ca. 0.2 mm[-1]) and that the laminae are not varves. The lack of varves is attributed to low sedimentation rates and variability in the sediment influx from year to year. Long cores (0.9-2.1 m) consist of finely to faintly laminated material, similar to modern sediments deposited below the chemocline. An abrupt colour change from predominantly black to olive brown occurs in two of the long cores at 37 cm and 120 cm. The colour change represents the transition from an oxidizing environment to an anoxic, reducing environment. A marine shell (Portlandia arctica), retrieved from long core #1 at 70 cm below the sediment surface yielded a 14C date of 3620+/-160 BP (TO-3759), indicating that prior to ca. 3600 BP, the Romulus Lake basin was an extension of Slidre Fiord, assuming the shell was in situ. During the period of isolation from Slidre Fiord due to glacioisostatic emergence, the Slidre River flowed into Romulus Lake, forming a prograding delta which acted to separate the basin from Slidre Fiord. The inflow of fresh water from the Slidre River during and after separation from Slidre Fiord diluted the surface water forming the mixolimnion while enrichment of the monimolimnion occurred.
Bibliography of Canadian Geomorphology