Continental slopes and the adjacent deep basins are the ultimate sink for glacigenic sediment that has been supplied to the glacimarine transfer zone, reworked, and advected to the more distal part of the system (Fig. 1 and Fig. 2E, F). Sediment cores and seismic facies in the deep sea reveal that gravity flows and hemipelagic settling are the main transfer mechanisms to these sinks (Fig. 1 and Fig. 11; Dowdeswell et al., 1996, Dowdeswell et al., 1998, Wilken and Mienert, 2006, Reece et al., 2011, Cofaigh, 2012, Garcia et al., 2012, Batchelor and Dowdeswell, 2014 and Walton et al., 2014). Debris flows are ubiquitous on continental slopes seaward of cross-shelf troughs that were occupied by ice streams (Fig. 10 and Fig. 11; Laberg and Vorren, 1996, King et al., 1998, Taylor et al., 2002a, Batchelor and Dowdeswell, 2014, Dowdeswell et al., 2014 and Rebesco et al., 2014). Deposition of debrites results in the formation of trough G007-LK fans, the primary depositional landform on many northern hemisphere margins (Vorren et al., 1998, Dahlgren et al., 2002, Elverh?i et al., 2002, Taylor et al., 2002a, Cofaigh et al., 2003, Dahlgren et al., 2005, Nielsen et al., 2005, Batchelor and Dowdeswell, 2014 and Rebesco et al., 2014). Trough mouth fans occur wherever slopes are < 4° (Cofaigh et al., 2003 and Batchelor and Dowdeswell, 2014); on steeper slopes, gravity flows supply sediment to deep submarine basins via large submarine channels (Dobson et al., 1998, Reece et al., 2011, Garcia et al., 2012 and Walton et al., 2014). Although gravity flows transfer large volumes of glacigenic sediment onto slopes and into deepwater basins (Reece et al., 2011, Garcia et al., 2012 and Walton et al., 2014), suspended sediment settling from turbid surface and intermediate water depth plumes dominates the temporal record in these settings (Taylor et al., 2002c). At shelf margins in Antarctica and NE Greenland, trough mouth fans are rare to absent (Livingstone et al., 2012 and Batchelor and Dowdeswell, 2014), and the prevalent gully morphology suggests that density flows drive near-bed sediment transport to deeper basins (Nielsen et al., 2005, Dowdeswell et al., 2008b, Noormets et al., 2009, Livingstone et al., 2012 and Gales et al., 2013). The lack of trough mouth fans in these settings may either reflect steeper continental shelf breaks or lower sedimentation rates than are required to construct a low-angle slope (Livingstone et al., 2012 and Gales et al., 2013). This observation suggests that reduced sediment fluxes from polar ice sheets influence continental slope morphology at the highest latitudes.
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