[dowling] cretaceous SEA IN ALBERTA 37 



it would seem that the Upper Pierre near-shore deposits were at one 

 time present over the Wapiti sandstones. This suggests that the 

 section in Table mountain, Pine river, consists of the following series 

 of deposits in descending order: — 



1. Marine sands (near-shore deposits of the western edge of the 

 Upper Pierre sea). 



2. Wapiti sandstones (shore deposits of the retreating stage of 

 the Lower Pierre sea). 



3. Smoky River shales (marine deposits of Lower Pierre sea). 



4. Dunvegan sandstones (shore deposits of early Pierre age). 



Nos. 2, 3 and 4 on this evidence may be correlated provisionally 

 with the Belly River series of southern Alberta. 



Lower Pierre (Belly River) Upper Shore Deposits. 



The beds included under this head embrace not only the shore 

 deposits during the retreat of the Lower Pierre sea, but also should 

 include, since they are intimately associated in the same sections, those 

 beds deposited above sea under the assorting action of freshwater 

 streams and lakes (see Plate VI). The lower members of the forma- 

 tion, which on the whole is wedge-like in its transverse section, are 

 mainly of brackish-water deposition and were referred to in the original 

 description as generally yellowish in colour. Freshwater deposits 

 occur in the upper or pale coloured beds although brackish-water 

 forms are found. Coal horizons of economic importance occur at the 

 top and also in the lower members. The estimated thickness for the 

 two classes of deposits must vary with the locality: a maximum for 

 the pale coloured beds may be given as 400 feet, and for the yellow beds 

 350 feet.i 



These estimates cannot be added together as it is not known 

 that the division is distinct enough to be recognized in areas remote 

 from each other. 



The upper part of the Belly River formation consisting of the 

 shore deposits of the retreating Lower Pierre sea has been correlated 

 by T. W. Stanton^ with the Judith River formation of Montana. 

 This correlation includes not only a similarity in the faunal remains 

 but also in the character of the deposits and was finally certified by 

 tracing in the field the connecting exposures. Similarly in western 



iRep. of Progress, 1882-83-84, pp. 116-117C. 

 2 Bull. No. 257, U. S. Geol. Survey. 



