696 INDEX TO THE STRATIGRAPHY OF NORTH AMERICA. 



On the North Saskatchewan and its tributaries TyrreJP'^ distinguished the 

 following beds: 



Laramie: Feet. 



Paskapoo series: Gray and brownish weathering lamellar or massive sandstones and oHve sandy 



shales. This is an exclusively fresh-water deposit 5,700 



Edmonton series: Soft whitish sandstones and white or gray, often arenaceous clays, with bands 

 and nodules of clay ironstone and numerous seams of lignite. These are of brackish-water 

 origin and correspond to the lowest portion of the St. Mary River series of Dr. Dawson's report 



(Geol. Survey, Kept, for 1882-84, p. 114c) 700 



Fox Hill and Pierre: Brownish- weathering sandstones and dark-gray clay shales 600 



Belly River series: Soft whitish sandstones and arenaceous clays, changing toward the east to light- 

 brownish and yellowish sandstones and sandy shales; bottom not seen. 



In the foothills evidence was found of the presence of rocks of the age of the Benton shales, 

 which ■ immediately underlie the sandstones of the BeUy River series, but our knowledge of 

 them is as yet too imperfect to allow of our treating of them in any way, and we can therefore 

 simply record their occurrence. 



No intrusive rocks occur anywhere throughout the district, and below the top of the 

 Laramie there is no evidence of any unconformity between the different formations, although 

 in some cases the extreme irregularity of the bedding gives the strata very much the appearance 

 of having been laid down unconformably one on the other. 



[The BeUy River series is represented by] white or hght-gray clays and soft clayey sandstones, 

 interbedded with bands and nodules of clay ironstone. These nodules are often highly cal- 

 careous, breaking with a smooth, sharp fracture. Toward the center, on a freshly broken sur- 

 face, they are of a clear slate-gray color; around are darker and darker layers, till the outer one, 

 which is very dark brown, almost black. 



As has already been pointed out in the reports of Dr. Dawson and Mr. McConneU, this 

 series, if followed toward the east, is found to lose gradually its clayey character and to consist 

 of purer and much more massive sandstones, generally of a yellowish color. 



The Fox Hill and Pierre are described by Tyrrell as consisting of — 



dark or hght gray, very friable clay shales, weathering down into a soft tenacious clay, inter- 

 bedded with bands of coarse-grained yellow sandstone. Unlike the beds both above and below, 

 it is of purely marine origin, having been laid down in a sea of varying though generally very 

 considerable depth. 



The thickness of the formation, wherever it could be measured, was found to be from 600 

 to 700 feet. 



It is quite impossible here to separate the Fox Hill sandstone from the Pierre shales, as they 

 are completely interbedded from the top to the bottom of the group. In descending Battle 

 River tliis is particularly noticeable, as at the top of the group yellow sandstones are met with 

 containing Placenticeras placenta, teredo burrows, etc., and at the bottom a sandstone quite 

 undistinguishable from that above is seen holding precisely the same fossils. In the southern 

 part of the district, nodules of clay ironstone are common throughout the shale, and fossils are 

 plentiful, both in the nodules and in thin bands of included sandstone, but to the northward, 

 fossils become much more rare and new species begin to appear, which are not known to the 

 south. 



The fossils found in the district, so far as known at the time of the report, are 

 listed by Tyrrell to the number of 32 species. 



No workable beds of coal occur in this group within the district, though in the shales on 

 the top of the high ridge to the north of the Neutral HUls a thin band of carbonaceous shale is 

 seen over a considerable area, and at Egg Creek, ,near the North Saskatchewan, there is a thin 

 seam of coal of fine quality. 



