| Summary: | Results from an investigation of relative sea-level changes from c. 11,000 cal. yr BP to the present in the Tasiusaq area, Inner Bredefjord, southwest Greenland, are presented in this thesis. Isolation sequences from two small lakes have been identified using stratigraphic analyses, XRF-scanning, loss on ignition and macrofossil analyses. Macrofossil and bulk samples have been dated in order to establish at what time the lake basins became isolated from the sea. These data have been combined with data from one marine embayment to establish the relative sea-level changes in the Tasiusaq area for the last 11,000 years. The data show that sea level fell rapidly in early Holocene and reached present-day level at c. 8050 cal. yr BP, and support earlier reconstructions of the ice sheet history showing that the ice sheet started receding at c. 22,000 cal. yr BP and that the ice-margin recession proceeded quickly: by c. 12,000 cal. yr BP the ice margin was inland of the present day coast and by c. 10,500 cal. yr BP it had reached the present-day margin. Sea level then continued to fall below 4.4 meters below highest astronomical tide in the area and reached its lowest levels between c. 7000 and c. 2000 cal. yr BP. The absolute lowest level of the post glacial sea level in the area can, however, not be established. As the Qaqortoq area further west and the Nanortalik area further south, the Tasiusaq area experienced a transgression in the mid- to late Holocene. In the Qaqortoq and Nanortalik areas this transgression started at c. 6000 cal. yr BP, while it seems to have started later (c. 4000 cal. yr BP) in the Tasiusaq area. This possibly reflects different forcing mechanisms working at different times between the sites; Nanortalik and Qaqortoq mainly being influenced by the collapse of the Laurentide peripheral bulge and Tasiusaq primarily being influenced by the re-advance of the Greenland ice sheet starting at the mid-Holocene climate deterioration. This new data from the Tasiusaq area can hopefully be used to improve ...
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