One indirect depositional proxy of episodic advance-retreat events on the continental shelf is the isolated hummocks and ridges found in many fjords or inner continental shelves, which are interpreted as push moraines during advance or morainal banks formed by bedload dumping at the terminus during retreat (Fig. 1 and Fig. 10; Dowdeswell and Vásquez, 2013, Landvik et al., 2014, Molnia, 1983, Ottesen and Dowdeswell, 2006, Ottesen et al., 2008a, Hald et al., 2001, Kristensen et al., 2009, Plassen et al., 2004, Kempf et al., 2013, Dowdeswell, 1995 and Dowdeswell et al., 2014). For the last LIA event, recent terminus retreat and lower post-LIA sedimentation rates allow for these GS-9820 landforms to be observed and mappable in swath bathymetry (Ottesen et al., 2008a). As noted by Boulton and Hagdorn (2006), such lobate landform features must be a consequence of local, fast ice streaming, where the response time of the ice dictates whether these features reflect a short-term surge event or a long-term occupation of the fjord by an ice stream. The challenge in using these features to quantify glacigenic sediment production during an event cycle is partitioning sediment that was previously deposited and has been remobilized and reworked into the morainal bank during the advance from newly-produced sediment that reflects the contemporaneous basal ice conditions and accounts for variable bedrock lithology (Fig. 12; Koppes et al., 2010).
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