GLACIAL HISTORY OF INTERIOR JAMESON LAND, EAST GREENLAND

The plateaus between 400 and 800 m a.s.l. around the water-divides on central and eastern Jameson Land are covered by the 'Jameson Land Drif t' - up to 50 m thick glacial, glaciofluvial and glaciolacustrine depo sits. A high content of far-travelled western rocks indicates the over riding by extensive glaciers channelled from the west through the Scor esby Sund basin. The Jameson Land Drift deposits have been lithostrati graphically divided into two groups, each representing the sedimentary successions from one glaciation - in the wider sense of the word. Sed iments from the lower Lollandselv glaciation are upwards delimited by a distinct periglacial surface. TL-dates suggest a pre-Saalian (approx imately isotope stages 11-9) age. The following Scoresby Sund glaciati on, when most of the studied Jameson Land Drift sediments were laid do wn, is of Saalian age (c. isotope stages 8-6). The deposits from the S coresby Sund glaciation are interpreted as representing a complete gla ciation-deglaciation succession, including proglacial sandur and glaci olacustrine sediments, followed by till deposition, with an overlying succession of glaciolacustrine and glaciofluvial sediments. From 200-2 50 m to c. 400 m a.s.l. there is a driftless area, exposing Jurassic s andstones, probably a result of intensive and long-lasting periglacial erosion. Extensive occurrences of tors and of glaciofluvially (subgla cially as well as subaerially) eroded canyons and channels characteriz e the landscape. A similar, although less well defined, upper driftles s zone is found above c. 500 m a.s.l. on northern Jameson Land, north of the drift-covered plateaus. During the Weichselian (isotope stages 5d-2), thick glacial, fluvial and marine deposits were laid down in a coastal zone below c. 200 m a.s.l., and only cold-based local ice caps seem to have existed on the interior plateaus of Jameson Land. The no w driftless areas were characterized by periglacial erosion during thi s period.