TH-230(EX) FLUX INTO NORWEGIAN-GREENLAND SEA SEDIMENTS - EVIDENCE FORLATERAL SEDIMENT TRANSPORT DURING THE PAST 300,000 YEARS

Th-230 was determined to investigate the influence of climatic cycles on the Th-230(ex) flux into Norwegian-Greenland Sea sediments. The F-a /F-p ratios, i.e., the ratios between the measured Th-230(ex) flux (F- a) into the sediments and the production rate of Th-230 in the water c olumn (F-p) vary considerably in the four cores investigated. Systemat ic variations in the ratios with the climatic cycles could not be obse rved. Furthermore, variations in the F-a/F-p ratios cannot be correlat ed between individual sites. It is argued that lateral sediment transp ort, due to deglaciation of ice sheets, bottom currents and/or downslo pe sediment transport, result in F-a/F-p ratios that are not equal to 1. The results suggest that both sediment winnowing (and/or erosion) a nd sediment focusing have strong influences upon sediment accumulation in the Norwegian-Greenland Sea.