Exposures at several localities in the Ottawa region reveal Champlain Sea deposits filling depressions on what were formerly submerged surfaces of Wisconsin sand and gravel ridges. The deposits, referred to as "kettle fill," constitute materials eroded from the ridges in a marine environment and redeposited in ice-melt depressions or kettle holes. Processes responsible for the deposition of the sediment appear to include debris flows and small turbidity currents initiated by wave washing and slope instability. The dimensions of the depressions, their depth in relation to the falling wave base, and the steepness of the flanks were important factors controlling sedimentation. The kettle-fill facies comprise diamicton (pebbly mud), gravel, sand, and lutite.

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