GLACIMARINE SEDIMENTARY PROCESSES AND FACIES ON THE POLAR NORTH-ATLANTIC MARGINS

Major contrasts in the glaciological, oceanic and atmospheric paramete rs affecting the Polar North Atlantic, both over space between its eas tern and western margins, and through time from full glacial to interg lacial conditions, have lead to the deposition of a wide variety of se dimentary facies in these ice-influenced seas. The dynamics of the gla ciers and ice sheets on the hinterlands surrounding the Polar North At lantic have exterted a major influence on the processes, rates and pat terns of sedimentation on the continental margins of the Norwegian and Greenland seas over the Late Cenozoic. The western margin is influenc ed by the cold East Greenland Current and the Svalbard margin by the n orthernmost extent of the warm North Atlantic Drift and the passage of relatively warm cyclonic air masses. In the fjords of Spitsbergen and the northwestern Parents Sea, glacial meltwater is dominant in delive ring sediments. In the fjords of East Greenland the large numbers of i cebergs produced from fast-flowing outlets of the Greenland Ice Sheet play a more significant role in sedimentation. During full glacials, s ediments are delivered to the shelf break from fast-flowing ice stream s, which drain huge basins within the parent ice sheet. Large progradi ng fans located on the continental slope offshore of these ice streams are made up of stacked debris hows. Large-scale mass failures, turbid ity currents, and gas-escape structures also rework debris in continen tal slope and shelf settings. Even during interglacials, both the marg ins and the deep ocean basins beyond them retain a glacimarine overpri nt derived from debris in far-travelled icebergs and sea ice. Under fu ll glacial conditions, the glacier influence is correspondingly strong er, and this is reflected in the glacial and glacimarine facies deposi ted at these times. (C) 1998 Elsevier Science Ltd. All rights reserved .