GEOLOGY AND PALEONTOLOGY OF THE SCHOHARIE VALLEY 245 



Feet Inches 



of the beds thin out altogether, and at 

 other times there is a rhythmic swelling 

 and thinning, suggestive of oscillation 

 ripples. A careful examination of the 

 weathered edges of these strata will give 

 one a good impression of the clastic char- 

 acter of these deposits. The wave action 

 is almost as marked in these beds as in 



Fig. 193 Ripple structure in Maniius. n, lime mudrock; b, lime sandrock 



any modern deposit of fine sand exposed 

 in road cuttings. 1 The bedding of the fine 

 lime mudrocks is such as to fill in by 

 horizontal layers the depression in the 

 lime sandrocks as shown in the annexed 

 diagram [fig. 193]. Layers of lime mud- 

 rocks are eroded to form ripples as shown 

 in figure 194. 

 Thickness of f 8 4 



Tig. 194 Ripple structure in Maniius lime 

 mudrock 



f G & f 7 Lime sandrock. in places almost made up of 

 Tentaculites ; Spirifer v a n u x e m i , 

 with rounded and not very strong ribs 

 occurs, approaching in character S. eri- 

 e n s i s 11 



'Some walls of the quarry, however, do not show this feature because 

 they are coated with a layer of calcite, formed there while the wall 

 bounded a joint fissure, by lime brought in in solution. 



