02788nas a2200289   4500000000100000000000100001008004100002653002000043653002400063653002100087653002800108653002300136653002300159100001700182700002200199700001800221700001600239700001800255700002000273700001700293245011400310856007100424300001000495490000800505520197100513020001402484       2004                            d10aGreenland Basin10aGreenland Ice Sheet10aLate Weichselian10aNorwegian-Greenland Sea10asubmarine channels10aturbidity currents1 aColm Cofaigh1 aJulian Dowdeswell1 aJeffrey Evans1 aNeil Kenyon1 aJustin Taylor1 aJürgen Mienert1 aManon Wilken00aTiming and significance of glacially influenced mass-wasting in the submarine channels of the Greenland Basin  uhttp://www.sciencedirect.com/science/article/pii/S0025322704000702  a39-540 v2073 aThe most extensive systems of submarine channels on the continental margins of the Norwegian\textendashGreenland Sea occur in the Greenland Basin (72\textendash75\textdegreeN). Geophysical records show that these channels are up to 100-m deep, 4-km wide, and extend for about 300 km from the middle continental slope off Northeast Greenland to the abyssal depths of the basin. Mass-wasting deposits in the form of debris flows and turbidity currents, as well as hemipelagic sediments, dominate sediment cores recovered from the channels. Radiocarbon dates indicate that debris flow and turbidity current activity in the channels had ceased by 13,000 years BP and sedimentation rates show a corresponding order of magnitude decrease after this time. Mass-wasting in the submarine channels of the Greenland Basin therefore relates to full-glacial and deglacial conditions. This implies a more extensive Late Weichselian ice sheet in Northeast Greenland than traditionally thought. The ice sheet extended onto the outer continental shelf and may have reached the shelf edge, delivering debris and sediment-laden meltwater onto the upper slope. Channel formation is most likely the product of turbidity-current activity during successive glaciations of the Northeast Greenland continental shelf. Holocene sediments from the channel systems are predominantly of hemipelagic origin and formed in a low energy, ice distal environment. The low gradient (1\textdegree) channels of the Greenland Basin are therefore a glacially influenced sedimentary system. Contrasts in slope morphology and sediment architecture between the Greenland Basin and trough-mouth fans elsewhere in the Norwegian\textendashGreenland Sea are not the result of variations in slope gradient. Rather, these contrasts reflect the interplay between bedrock lithology of the continental shelf, rates of sediment delivery, sediment texture, meltwater volume and relative size of ice-sheet drainage basins.  a0025-3227