GEOLOGY OF THE NEW YORK CITY AQUEDUCT 



55 



UNCONFORMITY 



Group d Devonic strata 



(6) Catskill, white and red conglom- 



erate (1725 feet) 



(7) Oneonta (upper flagstone) (3000 



feet) 



(8) Ithaca and Sherburne (lower flag- 



stone) (500 feet) 



(9) Hamilton and Marcellus shales 



(flagstone and shales) (700 

 feet) 



(10) Onondaga limestone (200 feet) 



(11) Esopus and Schoharie shales 



(silicious) (800 feet) 



(12) Oriskany and Port Ewen transi- 



tion (100 feet) 



(13) Port Ewen limestone and shale 



(150 feet) 



(14) Becraft limestone (75 feet) 



(15) New Scotland shaly limestone 



(100 feet) 



(16) Coeymans cherty limestone (75 

 feet) 



Confined to the Cats- 

 kills, the Esopus and 

 Rondout valleys, the 

 northern extension of 

 the Shawangunk 

 range, and Skunne- 

 munk mountain near 

 Cornwall 



(17) Manlius limestone (70 feet) 



(18) Cobleskill limestone and cement 



beds (30 feet) 



(19) Binnewater sandstone (50 feet) 



(20) High Falls shale, including small 



limestone beds (75-80 feet) 



(21) Shawangunk conglomerate (250- 



350 feet) 



Group e Sihiric strata 



Confined to the Rondout 

 and Esopus valleys 



and the northerly ex- 

 tension of the Shaw- 

 angunk range, 

 through the cement 

 region of Rosendale, 

 Binnewater, Rondout 

 and Kingston, and a 

 small outlier at Skun- 

 nemunk mountain 



