7 Paleoclimatology/Paleoceanography (Posters)

AN ANALYSIS OF VARVED SEDIMENTS FROM HIGH ARCTIC MURRAY LAKE, ELLESMERE ISLAND, NUNAVUT, CANADA

Paper number: 7-11
Program: Technical Sessions
Time: 8:00 AM – 12:00 PM

Authors

Abstract

The concerns involving recent and future climate change have placed considerable emphasis on developing climate records that encompass all regions of the world. In addition to modern climate records, there has been an emphasis on the recovery of high-resolution paleoclimatic records from regions that are highly sensitive to climatic change in order to gain an understanding of long term climate trends (Overpeck et al. 1997; Lamoureaux and Bradley, 1996). High Arctic lakes that contain annually laminated (varved) sediments have been shown to provide high resolution paleoclimate records on spatial and temporal scales that are important in studying climate variability (Hardy et al., 1996: Lamoureux and Bradley, 1996; Gajewski et al., 1997, Hughen et al., 2000; Lamoureux et al., 2001). For the purposes of this study, varves from short sediment cores taken from Murray Lake and Lake Tuborg are analyzed to eventually develop records of late Holocene paleoclimate variability.

Murray Lake is located on the eastern coast of Ellesmere Island at 81 20'N, 69 30'W. The lake is approximately 5 km2 and 50 m deep and lies 60 m above Archer Fjord. Runoff into the lake is dominated by nival melt from the west, spill over from the Upper Murray Lake to the north and a combination of nival and glacial melt from the Simmons and Murray Ice Caps to the east. Two short cores were retrieved from the northern basin in June of 2000 in 45 m of water. The short cores contain 1100 years of sedimentation and contain few disturbances or turbidites. During the field season of 2001 two long (5 meter) vibracores were retrieved from the deep basin.

This project intends to utilize the analysis of the short and long cores from Murray lake to develop a high resolution late-Holocene environmental record to study the temporal and spatial patterns of environmental change.