GEOLOGY OF OGDENSBURG 3I 



the additional advantage of having a large quantity of freshly 

 thrown-out rock rnaterial to examine. From the river level to the 

 summit of the hill; one mile east of Morristown, a 90 foot thickness 

 of rock is shown in the section, but only the upper 60 feet is in the 

 continuous section. The whole is so homogeneous in its alter- 

 nations of sandstone, calcareous sandstone, and sandy limestone, 

 that it seems better to generalize and simplify it, than to give the 

 entire, detailed section. 



Generalized section at Morristozun 



Thin-bedded, light-gray, somewhat magnesian lime- 

 stone, with frequent sand grains ; finely granular ; fre- 

 quent nodules of flesh-colored crystalline calcite, usu- 

 7. 6' ally small and elongated parallel to the bedding, but 

 sometimes an inch or more in diameter ; top not seen ; 

 an occasional thin layer of hard, calcareous sandstone is 

 interbedded with it. 



Thick-bedded, dark blue-gray, very sandy limestone, 

 alternating with grayish white calcareous sandstone, 

 both showing frequent cleavage surfaces of calcite, due 

 to cr^^stalline orientation of the calcite cement ; the blue 

 beds are full of thin black films of uncertain nature, 

 irregular but roughly parallel to the bedding; 'the sand- 

 stones are full of fucoidal markings, and both show 

 occasional, large, coiled gastropods. 



Limestone similar to that above, but alternating with 

 beds of white sandstone which are only slightly calcare- 

 ous ; the calcareous cement is present only in spherical 

 , spots, and elsewhere the cement is siliceous ; the cal- 

 ' careous cement weathers out, leaving brown, discolored, 

 weathered spots on the otherwise white surface; at 

 many horizons the sandstone is full of films of fine- 

 grained, greenish material resembling clay. 



Thin-bedded white sandstone, siliceous, but with 

 20' spots of calcareous cement which weather out leaving 

 round, brown spots ; Heuvelton sandstone. 



Alternating white sandstone and blue calcareous 

 sandstone, the former much in excess ; a bed of calcare- 

 10' ous sandstone at the base of the 20 foot sandstone, and 

 three others in the interval ; remainder all white sand- 

 stone. 



