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NEW YORK STATE MUSEUM 



Fig. 3 Diagrams showing the conditions of deposition of the sands and 

 claj^s of the Hudson valley and the development of the terraces 



No. I shows the ice lobe occupying the inner preglacial valley of the 

 Hudson and the waters (embayments of Lake Albany) filling the depressions 

 between the lateral margins of the ice lobe and the rim of the outer valley. 

 Deposits made in these waters were largely of sands. No. 2 shows the 

 shrunken ice lobe and the consequent broader embayments. Depositions of 

 flner sediments, mainly clays, were made in the deeper and more quiet waters. 

 No. 3 shows the conditions when Lake Albany was at the height of its 

 development. In the quiet mid-waters of the lake abundant clay sediments 

 were deposited. No. 4 shows conditions at the end of the first stage of 

 marked subsidence of the lake waters. The outer portions of the lake 

 bottom have emerged forming the present upper terrace. No. 5 shows the 

 conditions after the second stage of marked subsidence. The lower terrace 

 has emerged. No. 6 shows the deposits in their present relations and the 

 present topographical features of the valley. 



