Table 1. Pleistocene stratigraphy of the Boston Basin. 



Epoch 



Kaye(1961)' 



Judson (1949)2 



Upson and Spencer (1964)^ 



Holocene 





Upper peat 

 Marine silt 

 Lower peat 



Estuarine deposits 



Late Wisconsin 



Drift IV 

 Mostly outwash 

 (in Boston Basin) 



Lexington Outwash 



Outwash 



(Gary) 



Lexington Drift 



Mid Wisconsin 

 (Tazewell) 



Clay III 



Boston Clay 



Marine clay 



Early Wisconsin 

 (lowan) 



Drift III 



Boston TiU 



TiU 



niinoian 



Drift II 



Pre-Boston Till 



Bedrock 



niinoian 



or 

 Yarmouth 



Clay I 





Kansan 



or 



Nebraskan 



Drift I 







Bedrock 







1. Based on a section under Boston Commons, Massachusetts. 



2. Based on excavations at Boston, Massachusetts. 



3. Based on borings in fill of ancient valleys in the Boston Basin. 



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