CGRG Bibliography of Canadian Geomorphology
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Author : Bell, T.; Sheppard, K.; and Liverman, D.G.E.
Date : 1999.
Title : Stratigraphy and age of Quaternary sediments exposed along the coast of southern St. George's Bay.
Publication : Current Research Report, Government of Newfoundland and Labrador. Geological Survey. St. John's, NF, Canada.
Issue : 99-1:
Page(s) : 125-137.
Abstract
Almost sixty years after the initial mapping of extensive Quaternary sediments along the coast of St. George's Bay, a revised stratigraphic section is presented that identifies five main sediment types and their stratigraphical position along 39 km of coastline from Highlands to Flat Bay. The section displays varied sequences of glacial, glaciomarine, glaciofluvial and fluvial sediments, deposited during the late Wisconsinan glaciation and deglaciation of the coastal lowlands. These sequences are more complex than initially mapped, especially those associated with hummocky ridges at the coast. Evidence supporting a basal till (St. George's River Drift) overlain by a deltaic sequence (Bay St. George's Delta) could not be substantiated, whereas an upper till and ice-contact gravels (Robinson's Head Drift) related to a late glacial readvance were generally only associated with the ridge topography. Most of the exposed sediments have been deposited in an ice-proximal to ice-distal glaciomarine environment by debris flow, underflow, current flow or suspension settling. The complexity of the sedimentary sequences and the variability in depositional style associated with hummocky ridges are typical of grounding-line fans at a tidewater glacier margin. In contrast, sections remote from the ridges display a relatively simple deglacial sequence in a shallowing-marine to fluvial environment. Radiocarbon dates on marine shells suggest that both types of glaciomarine environment co-existed along the tidewater glacier margin between 14000 and 13500 BP.
Bibliography of Canadian Geomorphology