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Older classification. 



JoGGiNS Series. 



Late Pennsylvanian — 

 Shulie formation — 



(Thickness 2,136 ft. (658 m.) — Logan.) Permo-Carboniferous. 



Uplift and renewed erosion. 



Middle Pennsylvanian — 



Joggins formation — • 



(Thickness 6,886 ft. (2,099 m-) — Logan). Productive Coal Mea- 

 sures. 



Early Pennsylvanian — 



Boss Point formation — 



(Thickness 4,583 ft. (1,397 m.) — Logan). Millstone Grit. 



Disconformity. 



Mississippian — 



Windsor formation — 



(Thickness 2,000 ft. (610 m.), roughly Lower Carboniferous. 

 estimated.) 



Unconformity. 



CoBEQuiD Series. 



Pre-M ississippian 



Pre-Cambrian and pre-Devonian altered sediments. 



Pre-Cambrian and Palaeozoic igneous intrusives. 



The Joggins section is naturally divisible into five major 

 divisions, none of which is sharply delineated, but each is 

 the effect of peculiar conditions of sedimentation. These 

 are briefly: (a) a lower marine limestone and red shale 

 division of Mississippian age, called the Windsor formation ; 

 (b) a conglomerate, grey sandstone, and shale division of 

 Pennsylvanian age, of fresh -water origin, and containing 

 plant remains and thin coal seams, comprising the Boss 

 Point (Millstone Grit) formation; (c) a barren red shale 

 division included in the succeeding Joggins formation ; (d) 



