CGRG Bibliography of Canadian Geomorphology
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Author : Allard, S.
Date : 2003.
Title : Geochemistry, lithology and depositional history of the Rollingdam map area till, southwestern New Brunswick.
Publication : Unpublished MSc thesis. University of New Brunswick. Fredericton, New Brunswick.
Issue :
Page(s) :
Abstract
A total of 272 till samples were collected in the Rollingdam area of southwestern New Brunswick (NTS 21 G/06) and analyzed for patterns of glacial dispersal. The concentrations of 49 chemical elements and various clast lithologies as well as till fabric analysis were used to delineate the dominant glacial transport trajectories in an area of complex ice-flow history. The results of this study demonstrate that two depositional ice-flow events affected the study area during the Wisconsinan episode of glaciation. Chronologically, the early event flowed towards the southeast (~130° to 150°), while the later, much weaker event, followed a south-southwest trajectory (~210° to 220°). Both trends are apparent in the striae record and in the case of the southeasterly trend, dispersal is parallel to intensive megafluting and drumlinization. These trajectories correspond to ice-flow patterns described by previous workers who assign their ages respectively as Early Wisconsinan (>53 ka B.P.) and Late Wisconsinan (~15-13.5 ka B.P.). A single basal till unit of local derivation with texture and colour reflecting local bedrock units was encountered in the study area. The deposition of this till resulted from initial southeastward flowing ice and was later reworked (imprinted) by south-southwestward flowing ice.
Bibliography of Canadian Geomorphology