A reconnaissance study of Quaternary sediments exposed in coastal bluffs on eastern Graham Island has revealed the presence of two major till units, each of which is underlain by glaciomarine stony mud, outwash sand and gravel, and laminated to massive silt and sand of undetermined origin. Sediment units below the surface drift are older than the radiocarbon dating limit. Sediments above this drift provide a nearly continuous record of geologic events from before 16 000 years BP until the present.Stratigraphic evidence and radiocarbon dates indicate that: (1) late Wisconsin glaciation of the coastal lowlands of Graham Island was weak and of short duration; and (2) a period of low sea levels during late Pleistocene time was followed by a transgression that culminated about 7500–8000 years ago when the sea was about 15 m higher relative to the land than at present. Marine regression during middle and late Holocene time produced wave-cut scarps, wave-cut benches overlain by littoral sediments, bars, spits, and beach and dune ridges.

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