CANADIAN AND BLACK EIVER SECTIONS 167 



Lowville and Black River.^" These are iiiiquestionabl,y the deposits of 

 the western basin. The Eideau sandstone represents the basal Pamelia 

 sandstone. Only the thinned edge of the Pamelia limestone formation 

 appears here, if indeed it really occurs at all, which is to 1)0 expected, 

 since the invasion came from the south. On the other hand, the impure 

 reddish limestones, as the writer has seen them about Kingston, corre- 

 spond excellently lithologically with the pinkish beds in the upper divis- 

 ion of the Pamelia and are quite unlike any of tlie Lowville formation 

 on the ISTew York side. It may well be, therefore, that there is actiially 

 present here a thinned edge of the Pamelia formation, in which case 

 Ami's correlation of the Eideau sandstone with the Chazy would be 

 nearer the mark than the Black Elver age assigned to it by Wilson and 

 Grabau." 



Sections along the Black Eiver 



Following up the Black Eiver from the southeast corner of the 

 Theresa quadrangle, the trend is southeast, the south line of the Pots- 

 dam embayment is soon crossed, and the Potsdam and Theresa forma- 

 tions disappear. The direction is first east, or toward the supposed 

 Pamelia shoreline, and then south-southeast parallel with it. It is not 

 yet certain whether any of the Pamelia formation occurs up the vallej^ 

 or whether the Lowville rests directly on the pre-Cambrian. The nearest 

 approach to detailed work in the district known to the writer is the M^ork 

 of Sarle in 1896 for the geologic map. From his manuscript the follow- 

 in"- statements are taken : 



o 



"Three miles below Carthage the base of the Birdseye (Lowville) aud the 

 Calciferous sandrock (Beekmautowu) are exposed. In excavating a wheel 

 pit for a paper mill at this point, rock was removed to a depth of 6 feet beloxv' 

 the river level, the last 4 feet being a gritty sandstone of uniform texture, 

 weathering to a green or dull red color. This probably represents the upper 

 beds of the Potsdam. North of the paper mill a cut made in laying a branch 

 of the Clayton railroad exposed the upper layers of the Calciferous sandrock. 

 From the material of this excavation several specimens of ostracods wei'u 

 obtained." 



Carthage lies 10 miles southeast of Leraysville, which is on the Pamelia 

 formation near the east edge of the Theresa sheet (see map). Sarlc's 

 descriptions certainly suggest that his Potsdam is the Pamelia sandstone 

 aud his Calciferous the upper impure Pamelia limestone with its ostracod 



'" Bull, fieol. Soc. Am., vol. l.S. pp. .517, .518. 



"Canadian Record of Science, vol. is, p. 1.32. Bull. Geol. Soc. Am., vol. 17, p. 084. 



