Stratigraphy and origin of an area of hummocky glacial topography, northern Wisconsin, U.S.A.

J.W. Attig; L. Clayton

doi:10.1016/1040-6182(93)90054-j

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Stratigraphy and origin of an area of hummocky glacial topography, northern Wisconsin, U.S.A.

J.W. Attig·L. Clayton

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Abstract

The Winegar Phase of the Wisconsin Glaciation produced a band of hummocky glacial topography in northern Wisconsin. Some hummocks are composed of flow till and somewhat sorted till-like debris-flow sediment. These hummocks formed when ice melted beneath a cover of debris that flowed to its present position. Other hummocks contain interlayered lodgement and meltout till, flow till, debris-flow and slopewash sediment, lake, and meltwater-stream sediment. These hummocks formed where sediment was stacked near the ice margin. In other hummocks till and supraglacial debris-flow and slopewash sediment deposited during the Winegar Phase form a thin veneer over older meltwater-stream sediment. These hummocks formed when ice buried in pre-Winegar Phase stream sediment melted, and the overlying sediment collapsed. ?? 1993.

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J.W. Attig, L. Clayton. 1993. Stratigraphy and origin of an area of hummocky glacial topography, northern Wisconsin, U.S.A.. https://doi.org/10.1016/1040-6182(93)90054-j

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