SOIL TONGUES IN THE LEAMINGTON MORAINE, ONTARIO

W edge -shaped soil structures occur in many parts of southern Canada and the northern United States. These have usually been interpreted as being ice-wedge casts. Yehle (1954), however, has expressed concern over the confusion of fossil ice wedges with features he termed soil tongues, but also referred to as soil pendants (Wright 1961) or podsolschornsteine (Johnsonn 1959). Not only are soil tongues superficially similar to ice-wedge casts, but they also occur in temperate latitudes which may have experienced periglacial conditions during the Pleistocene. Soil tongues, however, are solutional features, formed by rainwater percolating through unconsolidated calcareous deposits. They may be distinguished from ice-wedge casts and other wedge-shaped structures by: (a) the presence of pebble or other marker beds extending unbroken across the wedges; (b) the absence of bed contortions or pressure features in the materials adjacent to the wedges; (c) their conical three-dimensional shape; and (d) the lower carbonate content in the sediments of the wedges than in the surrounding materials.