Late wisconsinan stratigraphy and chronology of southern St. George's Bay,Newfoundland: a re-appraisal

Almost sixty years after the initial mapping of extensive Quaternary sedime nts along the coast of St. George's Bay, Newfoundland, a revised stratigrap hic section is presented which identifies five main sediment types (diamict on, mud, sand, gravelly sand, gravel) and their stratigraphical position al ong 39 km of coastline from Highlands to Flat Bay. Most of the sediments ov erlying a basal till (St. George's River Drift) are interpreted to have bee n deposited in an ice-proximal to ice-distal glaciomarine environment by de bris flow, underflow, current flow, or suspension settling, and capped by g laciofluvial outwash (Bay St. George Delta). For the most part, sections di splay a relatively simple deglacial sequence in a shallowing marine to fluv ial environment. Where hummocky ridges intersect the coast, however, the se dimentary sequences are more complex and the variability in depositional st yle is typical of grounding line fans at a tidewater glacier margin. The oc currence of an upper diamicton or coarse gravels (Robinsons Head Drift) was generally observed only in grounding-line fan sequences and is interpreted here in the context of marginal fluctuations of a quasi-stable tidewater g lacier, and not necessarily a climatically-induced readvance of a land-base d ice margin (Robinsons Head readvance). Radiocarbon dates on marine shells from varied stratigraphic positions and sedimentary units suggest rapid de position occurred in a glaciomarine environment between 14 and 13 ka BP.