66 STANTON: UPPER CRETACEOUS STRATIGRAPHY 



water or continental deposits which, while very irregular and 

 varied, are yet uniform throughout in the character of their 

 variation. That the time equivalents of Claggett, Judith River 

 and Bearpaw, as well as the overlying Lance, are all included in 

 these non-marine deposits seems to me the most reasonable 

 assumption, tho it is perhaps not yet capable of complete proof. 



Another area in which there is a different development of the 

 rocks between the Eagle sandstone and the Bearpaw shale is the 

 Blackfeet Indian Reservation in Montana just south of the 

 Canadian boundary and east of the Rocky Mountain front some- 

 what more than 100 miles northwest of Judith. (Section No. 

 6, p. 59.) During the past two seasons the areal mapping and 

 detailed stratigraphy have been done by Mr. Eugene Stebinger 

 thru whose courtesy I am permitted to make these general state- 

 ments based on his detailed work and on data obtained during 

 two visits which I have made to the field. The Eagle sandstone 

 resting on Colorado shale with a low dip to the west is normally 

 developed and forms a conspicuous escarpment extending from 

 near Cutbank in a northerly or northeasterly direction to the 

 Canadian line. The Bearpaw shale of typical character and with 

 a marine fauna, here somewhat meagerly developed, is nearly 

 500 feet thick. Between these two formations there are almost 

 2000 feet of sediments in which no practicable formation bound- 

 aries can be drawn and which Stebinger has therefore mapped 

 as a unit altho it must include the time equivalents of both Clag- 

 gett and Judith River. Lithologically it has a closer resemblance 

 to Judith River and like that formation it is essentially non- 

 marine. It contains Unio, Viviparus, and other fresh-water shells 

 at various horizons from the top to within 200 feet of the base. 

 There are also dinosaurs and land plants, and locally thin brack- 

 ish-water beds are found with Ostrea, Corbula and Corbicula, 

 especially at the top and in the lower portions. No evidence 

 of marine fossils or sediments had been found in the formation 

 until September of this year when at the town of Cutbank I 

 found marine fossils locally abundant in a sandstone 50 feet 

 thick which forms the top of the east wall of the gorge of Cutbank 

 Creek about half a mile south of the town. The horizon is not 



