178 



Report of the State Geologist. 



Pittsfield. 



Pittsfield township, Otsego county, is on the eastern side of the Unadilla 

 river and lies east of the northern part of New Berlin and the southeastern 

 corner of Columbus. 



The line of division between the Hamilton and Sherburne formations 

 runs in a northeasterly direction along the side of the hill east of the Unadilla 

 river and Wharton creek to about two miles northeast of Pittsfield village, 

 when it takes a more easterly course across the divide between Wharton and 

 Butternut creeks. This line is twelve miles due north of that represented 

 as the top of the Hamilton formation on the "Preliminary Geologic Map 

 of New York 11 ; but this difference, which will be found across Otsego 

 count) and still farther eastward, is due to the fact that the Sherburne and 

 Ithaca formations were mapped as the upper part of the Hamilton in eastern 

 New York. 



Fossiliferous Hamilton shales and sandstones on the eastern bank of the 

 Unadilla river in the northwestern part of Pittsfield, as well as the barren 

 Sherburne shales and sandstones forming the long Pittsfield hill southeast of 

 New Berlin, crossed by the New Berlin and Morris road, the top of w hich is 

 capped by the Ithaca formation, were described by the writer several years 

 ago. 1 



The lower part of the hill east of Wharton creek and New Berlin village 

 shows ledges of arenaceous shales and thin sandstones which contain plenty 

 of characteristic Hamilton fossils. Above, and approximately 185 feet higher 

 than the railroad crossing below New Berlin, are thin, blue, unfossiliferous 

 sandstones and shales that belong in the Sherburne formation. This indicates 

 that the base of the Sherburne occurs at about the same elevation east of the 

 Unadilla river as in West creek in New Berlin village. 



XX F l . On the hillside east of Wharton creek, one-fourth mile north- 

 east of Pittsfield village and about iso feet above the railroad level of New 

 Berlin, are rough arenaceous shales containing numerous Hamilton fossils. 

 Ten feet higher are thin unfossiliferous sandstones w hich are perhaps in the 

 base of the Sherburne. The fauna of F 1 is as follow s : 



1. Spirifer {//■<(/! i/Io.shs (Con.), Hall. (a) 



2. Tropidoleptus carinatus (Con.), Hall. (aa) 

 ."». Ciji-tiiHt II<inrilt<>nensis,U'.i\\. (rr) 

 4. Aiiihocolia a inloiiata (Con.), Hall. (r) 



> Twelfth Annual Beport State Geologist [New York], pp. 188-186. 



