LINKING PHYSICAL PROPERTY RECORDS OF QUATERNARY SEDIMENTS TO HEINRICHEVENTS

Ice rafted debris in high latitude ocean sediments represent a complex record of the changing paleoenvironment of the oceans and, in particu lar, of the growth and decay of ice sheets along the margins of high l atitudes. Physical properties measured on sediment cores taken from th e Rockall Plateau were examined to determine the distribution of ice r afted debris layers and Heinrich events in the northeastern North Atla ntic. These sediment core records may provide one of the keys to recon struct the iceberg flow between the northeastern Atlantic and the Norw egian Sea. Magnetic susceptibility (MS) and Gamma Ray Attenuation Poro sity Evaluator (GRAPE) density changes of these cores revealed that si nce about 65 ka, dropstone layers are recorded in both MS and GRAPE da ta of Rockall Plateau sediments. Rockall Plateau sediments show peaks in physical properties that correlate with Heinrich events (H-1, H-2, H-4, H-5, H-6). Heinrich layer 3 was not observed. The stratigraphy an d physical properties represent the Heinrich layers: H-1 = 14-15 ka (M S = 52 mu cgs, rho = 1.64 g/cm(3)), H-2 = 23 ka (MS = 64 mu gs, rho = 1.8 g/cm(3)), H-4 = 41 ka (MS = 53 mu cgs, rho = 1.75 g/cm(3)), H-5 = 50 ka (MS = 53 mu cgs, rho = 1.75 g/cm(3)), H-6 = 64 ka (MS = 100 mu c gs, rho = 1.69 g/cm(3)). Heinrich events at Rockall Plateau sites poin t to a northward flow of icebergs in the northeastern Atlantic which m ay indicate a flow pattern to regions north of 54 degrees N.