Modern distributions of Arctic deep-sea benthonic foraminifera were examined from four expeditions -CESAR, LOREX, Fram I1 and 111. The samples covered a broad water depth range (800-4,200 m) and a wide range of Arctic environments from near the Fram Straits to the Alpha Ridge in the central Arctic basin. For the first time, diverse agglutinated assemblages were found in deep-sea Arctic material, near the Fram Strait in 800-1,000 m of water. We also observed a fauna unique to the deep Eurasian Basin (> 3,700 m) with 95%

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Core 86027‐144 (74°15.56′N, 91°14.21′W) represents a rare, continuous record of Late Pleistocene to Holocene sediments from High Arctic Canada extending from the end of the Last Glaciation. Based on microfossils (dinocysts, non‐pollen palynomorphs, benthic and planktonic foraminifera), foraminiferal δ18O and δ13C, and sedimentology, seven palaeoenvironmental zones were identified. Zone I (>10.8 cal. ka BP) records deglaciation, ice‐sheet destabilization, float‐off and subsequent break‐up. Zone II (c. 10.8–10.4 cal. ka BP) shows ice‐proximal to ice‐distal glaciomarine conditions, interrupted by pervasive land‐fast sea‐ice marked by a hiatus in coarse sediment deposition. Significant biological activity starts in Zone III (10.4–9.9 cal. ka BP), where planktonic foraminifera (Neogloboquadrina pachyderma) suggest early oceanic throughflow. Surface waters flowed NW–SE; however, the deep‐water origin remains unclear (potentially NW Arctic Ocean or Baffin Bay). Postglacial amelioration (open‐water season greater than present) in Zone IV (9.9–7.8 cal. ka BP) perhaps corresponds to the regional ‘Holocene Thermal Maximum’ previously proposed. A transitional period (Zone V; 7.8–6.7 cal. ka BP) of rapid environmental change fluctuating on a scale not observed today is marked by increasing sea‐ice and reduced oceanic influence. This probably signals the exclusion of deeper Atlantic water owing to the glacio‐isostatic shallowing of inter‐island sills, coupled with generally cooling climate. Conditions analogous to those at present, with increased sea‐ice and modern microfossil assemblages, commence at c. 6.7 cal. ka BP (zones VI–VII). Although climate ultimately forces long‐term environmental trends, core 86027‐144 data imply that regional dynamics, especially changes in sea‐level, exert a significant control on marine conditions throughout the Canadian Arctic Archipelago.

Marine geological and geophysical investigations were carried out in Wellington Channel, Byam Martin and Austin channels, and in eastern Barrow Strait-western Lancaster Sound from CSS HUDSON in i986. These investigations provided information on the distribution, thickness, composition, depositional environments, geotechnical properties, and regional geological setting of the surficial sediments, and on the structure of the near surface bedrock. The data indicate the widespread occurrence of sediments of apparent glacial origin (glacial drift) which overlie variably dipping sedimentary bedrock, and which are in turn locally overlain by up to a few metres of acoustically stratified and acoustically transparent sediments, interpreted to represent glaciomarine and postglacial sediments respectively. The drift unit locally forms constructional features interpreted to be moraines, and in places contains multiple sequences. Surficial sediment thicknesses in Wellington Channel commonly are less than JO m but locally reach 25 m, are somewhat greater in Byam Martin and Austin channels (up to 50 m), and are generally greater in eastern Barrow Strait, where they locally reach iOO m. Geotechnical, foraminiferal and textural data show consistent correlations with one another and with the acoustic stratigraphic units. The postglacial sediments have a high water content, low bulk density, and low shear strength; the converse applies to the glaciomarine and glacial drift sediments. Foraminifera are relatively diverse in the postglacial sediments, less diverse in the glaciomarine sediments, and are absent in the glacial drift. Magnetic susceptibility data suggest that most of the sediments probably were derived from Paleozoic rocks of the Arctic islands, but that glacial drift in northern Prince Regent inlet and glaciomarine sediments in eastern Barrow Strait-western Lancaster Sound may have been derived partly from Precambrian rocks bordering part of the Gulf of Boothia, south of Prince Regent Inlet. Some seafloor sediments, particularly the glacial drift, have been modified by ice scour.