CGRG Bibliography of Canadian Geomorphology
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Author : Evans, D.J.A.; and Campbell, I.A.
Date : 1992
Title : Glacial and postglacial stratigraphy of Dinosaur Provincial Park and surrounding plains, southern Alberta, Canada.
Publication : Quaternary Science Reviews
Issue : 11(5):
Page(s) : 535-555
Abstract
Thirty-one stratigraphic logs from the Dinosaur Provincial Park area reveal seven major lithofacies associations (LFA's). LFA 1 is a preglacial fluvial deposit recording deposition on a sandy braided floodplain. This LFA fines upwards to LFA 2, a glacilacustrine deposit, which records the first advance of Laurentide glacier ice into the region. Erosional contacts between LFA's 1 and 2 and bedrock suggest that large expanses of badlands may have existed prior to glaciation. LFA 3 is a grey till which, together with glacitectonized bedrock, records ice movement from the northeast. LFA 4 represents supraglacially derived diamictons and outwash. Its oxidized colour indicates either a considerable period of subaerial weathering or groundwater activity and the deposit is tentatively assigned an interstadial or interglacial age. A second glaciation is recorded by LFA 5 (heterogeneous diamicton) and LFA 6 (homogeneous diamicton). LFA 5 records a period of subglacial molding and then cavity filling by fluvial and debris flow deposits. LFA 6 records lodgement and melt-out of the same glacier ice after it had glacitectonically thrust large rafts of older LFA's. The sequence of molding-cavity fill- tectonism-melt out represents large scale decoupling of the glacier from its bed and later surges, creating extensive deformation of the substrate. Melt-out was interrupted in some places by remobilization caused by surges which continued throughout ice retreat. LFA's 7a-7e record deposition in glacilacustrine, fluvial, pond and aeolian environments after deglaciation. Some previously reported and new radiocarbon dates on regional and local surface drainage are discussed with reference to fluvial incision and Holocene climate. All LFA's are tentatively correlated with stratigraphic sequences reported from adjacent areas of southern Alberta and former regional glaciodynamics are assessed.
Bibliography of Canadian Geomorphology