46S T. C. Brown — Shaiaangunk Conglomerate. 



The following measurements made from core borings at the 

 points indicated on the accompanying cross section (fig. 2) will 

 show how variable these beds are within narrow limits: 





Overlying 







Binnewater 



High Falls 



Shawangnnk 



Hole No. 



material 







sandstone 



shale 



conglomerate 



6 



514 



drift 



& 1. S, 



(142' not 



separated) 





32 



240 



a 





a 



55 



67 



133* 



35 



248 



a 





a 



52 



82 



5* 



10 



238 



a 







62 



99 



5* 



12 



78 



a 







70 



90 



6* 



14 



67 



(i 









44* 



O 



23 



21 



a 











284 



20 



38 



a 









3* 



268 



11 



6 



a 









68* 



345| 



36 



54 



a 









20* 



409f 



38 



31 



a 









59* 



6* 



19 



100f 



Hudson 



River 







295 



27 



221f 



a 





u 







78+ 



A (*) indicates that the boring did not penetrate the full thickness of the 

 bed. 



A (f) indicates that the position or thickness was due to faulting. 



(|) This value was greater than the normal thickness of the formation 

 because of the angle of dip. 



Fig. 2. 



000 — 



400 - 



zoo _ 





Pr.ft 

 tttcnt 



//,*..„ /?,-,,, 



-600 

 -690 • 



Fig. 2. Geologic section along a portion of the Roudout tunnel line. Ver- 

 tical scale two and one-half times the horizontal. 



From these measurements it is evident that the approximate 

 thickness of the Binnewater sandstone is 55 to 60 feet. In 

 hole 12, where the thickness is given as 70 feet, the underlying 

 shale is thinner than in the adjacent hole 10, so that an error 

 may have been made in drawing the line between these two 

 members when examining the core. If this be true, then the 

 thickness of this formation varies from 52 to 62 feet for this 

 vicinity. This measurement agrees very closely with a 

 measurement made in the gorge of the Rondout below the 

 falls. 



