Glaciers which terminated near a salt water body often deposited considerable volumes of material directly in the water. This material may be deposited as till: ground moraine, terminal moraine, or drumlins. Glacial outwash may also deposit large quantities of sand and gravel near the terminal zone or silt and clay at greater distances. Due to the salinity of the depositional environment, the particles of clay may tend to flocculate (clump together) when deposited. If the salt water in the pores is later replaced by fresh water, the soil structure may become unstable and possibly flow. The quick clays in Norway and some Boston blue clays exhibit this behavior.
Glacio-marine deposits contain the fossils of salt-water plants and animals while glacio-lacustrine deposits only contain freshwater species.
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