Abstract The papers in this volume are the outcome of a Geological Society (London) meeting concerning glacier-influenced sedimentation on high-latitude continental margins, held at the University of Bristol, UK, in 2001. Since the publication of the Geological Society Special Publication Glacimarine Environments: Processes and Sediments (Dowdeswell & Scourse 1990), the intervening 11 years have seen a significant increase in research into the processes and patterns of glacimarine sedimentation, and the relationship between ice dynamics and the sediments and landforms preserved in the glacimarine environment. In this introduction, we outline the papers that make up the volume and we highlight the main findings and significance of each. First, however, we highlight three areas relating to sedimentation in glacimarine environments where we believe significant progress has been made in the last 11 years. These are: (1) glacially-influenced continental slope sedimentation; (2) iceberg-rafting processes and events; and (3) reconstructing the dynamics of former marineterminating ice sheets from glacial geomorphological evidence on continental shelves. Each of these areas is represented by papers in this volume.

Abstract Geological evidence indicates that sediment reworking is common around the continental margins and abyssal depths of the Norwegian–Greenland Sea, a high-latitude setting with glacier-influenced margins. Detailed analysis of 22 cores up to 5 m long, placed in context by accompanying geophysical data including high resolution sub-bottom profiles, swath bathymetry and backscatter maps, indicates that reworking is variable and ranges from debris flows and turbidity currents, to bottom-current activity, as well as iceberg scouring. Reworking by debris flows appears to be restricted mainly to the main trough-mouth fans and sediment slides. Elsewhere, turbidity-current activity frequently dominates, although iceberg ploughing down to 600 m depth and current winnowing assume increasing significance on continental shelves. Reworking in the Norwegian–Greenland Sea reflects variations in ice-sheet dynamics that, in turn, influence the rate of sediment delivery and location of depocentres. Spatial variations in the style of reworking may also reflect the influence of continental slope gradient and bedrock geology on continental shelves. The widespread nature of sediment reworking has important implications for palaeoceanographic investigations in the region, as reworking can result in erosion and disturbance of the sediment column. It is estimated that less than 7% of material delivered to the Norwegian–Greenland Sea since the Late Weichselian is derived from hemipelagic and pelagic sedimentation. This problem is significant where continuous, high-resolution records of hemipelagic and pelagic sedimentation are required, and attempts are made to correlate with other high-resolution proxy records, such as ice cores, at sub-millennial scales. Bioturbation results in the smoothing of high-resolution records and imposes a maximum resolution for sediment-core time-slices of generally 400 years or more. In the Norwegian–Greenland Sea, areas of high sedimentation such as trough-mouth fans or contourite drifts are commonly associated with extensive reworking. Identification of reworking is particularly important where attempts are made to link records of iceberg-rafted debris to past ice-sheet dynamics, as bottom-current winnowing and mass-flow processes can increase the concentration of coarse-grained iceberg-rafted debris. Such localized accentuation of the iceberg-rafted debris signal may lead to erroneous palaeo-environmental interpretations. It is therefore critical that palaeoceanographic interpretations are firmly underpinned by an explicit sedimentological assessment of reworking.