Moraine and terrace sequences in the upper Fraser River valley indicate four periods of major glacier expansion during Quaternary time. A well-developed soil on the west Tabernash terrace suggests a long period between the two most extensive ice advances. The first 14C dates from a multiple till sequence in the Front Range indicate that the local “Pinedale Glaciation” lasted from >30,000 to 13,700 B.P. Interstadial lake sediment, interbedded with the tills, is dated at 30,000 B.P. The latest advance from Jim Creek valley did not reach the Mary Jane site, and peat accumulation at the site began about 13,700 B.P.

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