* Corresponding author. - Present address: Royal Observatory of Belgium, Avenue Cir- culaire 3, B-1180 Brussels, Belgium. Quaternary Science Reviews, Vol. 17, pp. 155—184, 1998  1998 Elsevier Science Ltd. Printed in Great Britain. All rights reserved. 0277—3791/98 $19.00 PII: S0277–3791(97)00068-1 LATE CENOZOIC SEISMIC STRATIGRAPHY AND GLACIAL GEOLOGICAL DEVELOPMENT OF THE EAST GREENLAND AND SVALBARD–BARENTS SEA CONTINENTAL MARGINS ANDERS SOLHEIM-*, JAN INGE FALEIDE‡, ESPEN S. ANDERSEN, ANDERS ELVERHØI‡, CARL FREDRIK FORSBERG-, KRIS VANNESTE , GABRIELE UENZELMANN-NEBEN, JAMES E.T. CHANNELL -Norwegian Polar Institute, P.O. Box 5072, Majorstua, N-0301 Oslo, Norway (E-mail: anders.solheim@jsi.no) ‡ Department of Geology, University of Oslo, P.O. Box 1047, Blindern, N-0316 Oslo, Norway  Norsk Hydro A/S, P.O. Box 200, N-1321 Stabekk, Norway  Renard Centre of Marine Geology, University of Gent, Krijgslaan 281, B-9000 Gent, Belgium  Alfred Wegener Institut fu ( r Polarforschung, Columbus Center, D-2850 Bremerhaven, Germany  Department of Geology, University of Florida, Gainsville, Florida 3L611, U.S.A. Abstract—The European program on the Late Cenozoic evolution of the Polar North Atlantic Margins (PONAM), running from 1990 to 1994, resulted in a wealth of seismic data and sediment cores, particularly from the Svalbard and Barents Sea continental margin, but also from areas of the East Greenland margin. Deep sediment coring was undertaken on both margins during ODP Legs 152 and 162. This paper uses the PONAM-generated information as well as previous and subsequent seismic and core data, to review our present understanding of the glacial geological development of these regions. Four main depositional facies have been identified. These are represented by hemipelagic, glaciomarine sediments, sandy, silty debris flows, diamictic debris flows and tills deposited directly beneath grounded ice. The temporal and spatial distribution of these four facies determines the architecture and seismic character of the two continental margins. The two regions show significant differences, with regard to both the timing of initial glaciation and the response of the ice sheets to climatic variability. Glacial deposition has taken place on the East Greenland margin at least since 7 Ma, but apparently only since 2.5 Ma on the Svalbard—Barents Sea margin. Significant glacial expansion across the continental shelf prob- ably occurred in the early and late Pliocene in East Greenland, whereas the glaciers on Svalbard and the Barents Sea did not reach the shelf edge until the early Pleistocene. Despite a shorter glacial period, average glacial sedimentation rates are 2—3 times higher on the Sval- bard—Barents Sea margin than on the studied parts of the East Greenland margin. The Svalbard—Barents Sea ice sheet has advanced and retreated much more frequently during the Plio—Pleistocene than the Greenland ice sheet. Glacial regime (polar on Greenland and polythermal to temperate in Svalbard and the Barents Sea) and the more easily erodible preglacial bedrock of Svalbard and the Barents Sea are thought to be main factors responsible for the differences in ice sheet behavior and, consequently, glacial sediment pro- duction.  1998 Elsevier Science Ltd. All rights reserved. INTRODUCTION The term ‘glacial continental margins’ is used here for continental margins affected by ice sheets which at regular intervals have been grounded on the continen- tal shelf. Typically, these margins are found in present- ly glaciated regions, such as adjacent to Antarctica, Greenland, Alaska, the Canadian Arctic and Svalbard. Whereas Antarctica and Greenland still hold extensive ice sheets, many areas covered by Plio and Pleistocene ice sheets, such as Svalbard and the Barents Sea, Fen- noscandia and northern North America are de- glaciated or only partly glaciated today. Adjacent gla- cial continental margins have sedimentary records with predominantly glacial deposits, whereas inter- glacial sediments are sparse and present sedimentation rates low. The direct action of ice is responsible for the main differences in depositional environment between gla- cial margins and lower latitude, non-glacial mar- gins. Importantly, during Plio—Pleistocene eustatic 155