Abstract

A belt of oriented till ridges along the southern margin of the St. Lawrence Valley, New York, is shown to be similar in form and occurrence to Swedish Rogen moraine, Canadian ribbed moraine, and Finnish hummocky active ice moraine. It is the first such occurrence described in the United States and is of interest because of the sequential development of moraine, drumlins, drumlinoid molding, and/or flutings. At low elevations the belt consists of a ribbed moraine that is smoothsided, in various stages of drumlinoid molding, or composed entirely of small, en echelon drumlins. At higher elevation the moraine is reoriented and streamlined to form large drumlins. It is proposed that the ribbed moraine and drumlins formed subglacially during one ice advance (Fort Covington) and not by accumulation and overriding at the foot of the glacier as previously proposed.

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