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Geomorphology 75 (2006) 212¨C 225
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MORPHOLOGY AND GPR STRATIGRAPHY OF A FRONTAL
PART OF AN END MORAINE OF THE LAURENTIDE ICE SHEET: PARIS MORAINE NEAR GUELPH,
ON, CANADA
S. Sadura1,
I.P. Martini1, A.L. Endres2
and K. Wolf3
1University
of Guelph, ON, Canada
2University
of Waterloo, ON, Canada
3Stanford
University, CA, U.S.A
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 During
deglaciation, the Laurentide Ice Sheet developed lobate ice termini in the Great
Lakes area. Where the lobes remained quasi-stationary for considerable time and
sediment was supplied by the glacier, end moraines fronted by outwash plains
were formed. One of the best examples in southern Ontario is the Paris Moraine
formed by the Lake Ontario lobe. This study is a detailed examination of the
morphology (transverse and longitudinal) of part of the Paris Moraine near
Guelph, Ontario, and an analysis of the stratigraphy as derived from borehole
information and Ground Penetrating Radar (GPR) surveys. Parts of the
northwestern frontal zone of the moraine are characterized by c. 30 m high,
semi-isolated hills composed in great part by aprons (fans) of debris-flow and
waterlaid sediments. To the southeast, these hills are backed by moat-like
depressions similar to those formed by ice-push, generating hill-hole
morphology. The ice-push effect is corroborated by evidence of folding and
dislocation in the GPR profiles. Farther southeastward still, the main body of
the end moraine is characterized by hummocky-topography typical of differential
melting of sediment-charged stagnant ice.
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