DISTRIBUTION OF CLAY-MINERALS IN SURFACE SEDIMENTS FROM THE EASTERN BARENTS AND SOUTH-WESTERN KARA SEAS

Surface samples from the eastern Barents and south-western Kara seas h ave been analysed for clay mineralogy. Transport paths, the role of re gional sources and local bedrock outcrops and the influence of hydrody namic and glacigenous processes for clay distribution on the shelves a re discussed in relation to central Arctic Ocean deep sea and sea ice sediments. Franz Josef Land and Novaya Zemlya show significantly diffe rent clay mineral associations. Although smectite concentrations are f airly high, Franz Josef Land can be excluded as a source for central A rctic sea ice sediments, which are relatively rich in smectite. In the Kara Sea, smectite concentrations in coastal sediments surpass even t he Franz Josef Land concentrations. The large cyclonic gyre in the eas tern Barents Sea between Novaya Zemlya and Franz Josef Land, which ser ves as a mixing zone between Arctic and North Atlantic water, is appar ently reflected within the smectite distribution pattern. With the exc eption of Franz Josef Land, the area of investigation is typically low in kaolinite. In particular, coastal areas and areas north of Novaya Zemlya, influenced by the inflow of Arctic waters, show the lowest kao linite concentrations. A high kaolinite occurrence within the Nansen B asin is most probably related to Franz Josef Land and emphasizes the i mportance of long-range downslope transport of sediments across the co ntinental slope. The surface water circulation pattern in close intera ction with local outcrops onshore Novaya Zemlya and locally restricted occurrences within the eastern Barents Sea significantly alter the il lite dispersal pattern. Illite concentrations are lowest around Franz Josef Land. Chlorite is generally low in the area of investigation. Su bmarine outcrops and important chlorite occurrences onshore Novaya Zem lya bias its distribution pattern.