Icecontact glacimarine and glacilacustrine landforms

Information on glacimarine and glacilacustrine sedimentation from subpolar glaciers in the Canadian High Arctic is largely based on investigations of emergent Holocene sediments (e.g. 0 Cofaigh et al., 1999; Smith, 2000). Where subpolar glaciers terminate in marine environments, englacial and subglacial meltwater emanating from these ice-masses forms subaqueous grounding-line fans, ice-contact deltas and morainal banks. Spatially, the location of these subaqueous depocentres exhibits a strong relationship to fjord bathymetry. Grounding-line fans form where sedimentladen meltwater enters deep water from englacial or subglacial conduits. Morainal banks are deposited along grounding lines during glacier stillstands. They range in height from about 5 to 30 m, and their elongate morphology reflects deposition from point sources along the ice-front, as well as ice-marginal fluctuations that bulldoze and squeeze sediment. Where grounding-line fans and morainal banks aggrade to sea level, they form marine limit deltas (Fig. 19.2). Distinguishing characteristics are steep ice-proximal slopes and kettled surfaces due to melt-out of buried ice.

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