CGRG Bibliography of Canadian Geomorphology
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Author : Butler, D.L.; and Wolfe, A.
Date : 1993
Title : Sedimentological, palynological and diatom evidence of the Younger Dryas, Pine Hill Pond, Terra Nova National Park, eastern Newfoundland.
Publication : Atlantic Geology
Issue : 29(2):
Page(s) : 159
Abstract
The basal 150 cm of lacustrine sediment in a core from Pine Hill Pond, Newfoundland, includes the late-glacial and early Holocene and contains strong sedimentological and paleoecological evidence for a climatic oscillation equivalent to the Younger Dryas. Basal late-glacial minerogenic sediments are overlain by a silty gyttja marking the onset of organic sedimentation, but an overlying unit comprising 7 cm of silty clay marks a brief reversion to mineral sedimentation, prior to subsequent uninterrupted deposition of organic sediments. During this phase, the reversion from shrub tundra to a sparser herb-shrub tundra pollen assemblage (Oxyria digyna, Artemisia) is a strong indicator of climatic deterioration at the site. The paleolimnological expression of the Younger Dryas at this site is manifested by a sharp decrease of diatom concentrations followed by decreases in the relative frequencies of Fragilaria spp., which are largely replaced by a stratigraphically restricted group of unusual benthic forms, a rise in the relative frequency of chrysophyte cysts, and a crash in Pediastrum concentrations.
Bibliography of Canadian Geomorphology