Site Desrciption

Murray Lake (81°20’N, 69°30’W, 106 m a.s.l)
Upper and Lower Murray Lakes occupy a glacially carved valley, 5 km from Archer Fiord on northeastern Ellesmere Island, Nunavut Canada. The two lakes occupy a drainage area covering approximately 269 km²>. The majority of this area (~194 km²) drains directly into Upper Murray Lake which is connected to Lower Murray Lake by a shallow (<0.5 m) stream. Two small (~2.5 km²), stagnant ice caps are located to the east of Lower Murray Lake. Although the two ice caps drain predominantly into Lower Murray Lake, there may have been drainage directly into Upper Murray Lake when ice margins expanded during the Little Ice Age. A larger ice cap (~15 km²) located to the south west drains into Upper Murray Lake. The lakes themselves are similar in size with surface areas around 6 km²>. The maximum depth of Upper and Lower Murray Lakes are ~80 m and ~45 m, respectively. Both lakes are depleted in oxygen near the sediment water interface, and clastic laminations are well preserved in the sedimentary record.

Sawtooth Lake (79° 20’N, 85° 51’W, 280m a.s.l.)
Sawtooth lake is the highest of three lakes situated within a col in the Sawtooth Mountain Range on the Fosheim Penninsula in central Ellesmere Island. The surrounding region is mountainous, with over 1000 m of relief. At present, there are no glaciers within the watershed and the lake is fed mainly by snowmelt, through a single main tributary at the lake’s eastern end. The 2.6 km²> lake has two deep basins, 80 m and 100 m deep, separated by a 60m deep sill. The distal basin is depleted in oxygen and contains annual clastic sediment laminations. Sawtooth Lake is located ~60 km southeast of Eureka, the site of the nearest weather station. Summer temperatures in Eureka average 5.5° C, with a mean annual temperature of -20° C. The area is considered a polar desert, with annual precipitation (predominantly snow) averaging only 68 mm.

Lakes C1, C2, and C3 (82° 50’N, 78° 00’W)
Lakes C1, C2, and C3 are low elevation lakes (<10 m a.s.l.) located along Taconite Inlet, a north-facing fiord, on the north coast of Ellesmere Island. This region is part of the Challenger Mountain Range and local relief exceeds 1250 m. The north coast is isolated from the rest of Ellesmere Island by the ice-covered Grant Land Mountains to the south, which reach elevations greater than 2500 m. The Holocene marine limit in the region is ~75m a.s.l. and the lakes of Taconite inlet are density stratified with saline water at depth. Anaerobic conditions have been recorded close to the sediment water interface in all three lakes. Climate in Taconite Inlet can be characterized as a maritime polar desert. Monthly mean temperatures at the nearest weather station (Alert: 82° 30’N, 62° 20’W, 63m a.s.l ~230 km east of Taconite Inlet) range from ~ -33° C (February) to ~ +4° C (July). Lake C1, the northernmost lake, has the smallest of the three drainage basins (3.7 km²) and receives very little runoff; what enters the lake is largely by overland flow from snowmelt around the lake, or from one small (snow-fed) stream. The lake has a surface area of 1.1 km² and maximum depth of 65 m. Lake C2 has a surface area of 1.8 km² and is 84 m deep. The 26.6 km² drainage basin is mountainous, with extremely steep slopes. The lake receives runoff from glaciers upstream, as well as snowmelt from surrounding slopes. The bulk of the water and sediment entering the lake does so via the primary inlet to the east. Lake C3 has a surface area of 1.7 km² and has a maximum depth of 51 m. The main river entering Lake C3 today drains terrain similar in relief to the main drainage into C2. Although the modern watershed is ~ 10.8 km², the Taconite River (~250 km² drainage) must have discharged a large volume of water and sediment into Lake C3 at some time in the past, because many abandoned channels form the southwestern margin of the lake. Unlike Lakes C1 and C2, the water of Lake C3 is essentially fresh and chemical stratification is weak – presumably because the lake was flushed clear of marine water by the large influx of glacier meltwater from the Taconite River at some point in the past.