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Rapid variations in climate through glacial periods have been associated with changes in ocean conditions. Modelling iceberg flow and melt is critical to evaluating their role in perturbing the state of oceans during glacial periods and subsequent deglaciation. This thesis aims to quantify the spatial and temporal history of icebergs flow, melt and sedimentation after release from the Eurasian Ice Sheet during the last deglaciation. The research structure required to meet this aim is in three steps. First, results from a numerical ice sheet model were processed in order to use them as input to an iceberg flow model. Other model inputs, such as topography and ocean and climate forcing fields, were also collated and input. Second, an iceberg model was compiled so that iceberg melt and sedimentation could be evaluated in the late glacial Nordic seas. Third, knowledge of the marine sedimentation record was built in order to compare with model results. This comparison allowed a number of literature-based hypotheses to be tested. This thesis has revealed the following results. The model showed that Eurasian icebergs may only be delivered to the North Atlantic under glacial ocean and atmospheric conditions. Under conditions similar to today, icebergs are restricted to the northern waters of the Nordic seas. The model also revealed that iceberg meltwater does not have a simple-distance-decay relationship. Instead, the pattern of meltwater release was found to be influenced by iceberg convergence zones; a consequence of the iceberg response to atmospheric and oceanic forcing. The model results also demonstrated that the locations of iceberg meltwater did not always coincide with modelled IRD. Consequently, the absence of IRD in the marine sedimentary record should not necessarily be interpreted as an indicator of absence of former icebergs. Models of the ice-ocean-atmosphere currently treat iceberg meltwater input in a simple way. The results presented here may be used in further numerical investigations of the processes responsible for rapid climate change in the last deglaciation.

This study concerns the Pleistocene drainage evolution of the lower reaches of the Rio Almanzora in the Vera Basin, SB Spain. Although the principal aim is to establish the relative importance of tectonics, climate and sea-level controls on the development of this fluvial system, the results contribute to a much wider debate concerning the nature of fluvial system evolution.

The continental margin in the area west of Shetland was subjected to repeated and extensive ice sheet advances during the Late Pleistocene. Seabed imagery, seismic survey and borehole core data show the Late Devensian ice sheets expanded across the continental shelf three times, two of these advances reaching the shelf edge. On the inner shelf, where present-day water depths are generally less than 100m, only thin sediments from the last retreat phase and exposed rock surfaces remain, all other deposits from earlier phases having been removed by the last advance. On the mid to outer shelf elements of all three phases are preserved, including lodgement and deformation tills, melt-out and water-lain till sheets, in-filled hollows left by stagnant ice decaying in situ and a series of large recessional and terminal moraines. In addition, there is evidence of shallow troughs and overdeepend basins which indicate preferential ice-drainage pathways across the shelf which were formerly occupied by ice streams. At the shelf edge, a thick wedge of glacigenic sediment forms a transition from the till sheets and moraines of the shelf to debris flows composed of glacigenic sediments on the upper slope. Shelf-edge moraines show an architecture indicating floating ice in modern water depths over approximately 180m, suggesting the West Shetland ice sheet was no more than about 250m thick. The upper and middle slope is dominated by glacigenic debris flows which are focused in the slope areas below the proposed ice stream discharges at the shelf edge. The mid-to-lower slope has been subjected to contour current activity which has re-worked much of the glacigenic sediment in this position. The lower slope and floor of the Faroe-Shetland Channel are marked by either large debris flow lobes of glacigenic sediment or thin glacimarine muds deposited from suspension. A conceptual model of the glacigenic development of a passive continental margin based upon the West Shetland example shows the deposited sequence for both advance and retreat phases of a glacial cycle, and the actual preserved sequence which might be expected in the rock record. The model also shows that ice sheet buoyancy, thickness, and to a lesser extent, basin subsidence, are the most important factors in the deposition and preservation of a glacially-influenced marine sequence.