Sedimentation and Physical Limnology in Proglacial Malaspina Lake, Alaska.
MASSACHUSETTS UNIV AMHERST COASTAL RESEARCH CENTER
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Glaciolacustrine varved sediments are presently being deposited in Malaspina Lake, which lies along the southeastern margin of the Malaspina Glacier. Malaspina Lake waters exhibit a reverse thermal stratification. Two large surface streams, Russell Stream and Tarr Stream, flow into the lake and their combined discharge is 140 cms. Discharge from the lake is as much as 600 cms, thus subglacial and englacial streams apparently discharge as much as 460 cms into the lake. Bottom topography of the lake is quite irregular except where the selective infilling of basins by turbidity currents has produced flat to gently sloping topography. Cores taken of these flat areas contain varved sediments. Varves, deposited at depths of 50 m or more, contain normal and reverse graded beds and horizontal beds. The current-bedded portion of the varve was deposited from an underflow or turbidity current. The varve was completed by the deposition from suspension of a clay unit when continuous underflows, or turbidity currents, ceased during the winter months.
- Geology, Geochemistry and Mineralogy
- Hydrology, Limnology and Potamology