NO. 5 PRE-DEVONIAN PALEOZOIC FORMATIONS 329 



Feet Meters 



The limestones rest on the somewhat hummocky 

 and uneven surface of the subjacent Mount Wilson 

 quartzite, which is all that there is representing the 

 Ghost River formation between the base of the Devo- 

 nian and the subjacent massive limestones of the 

 Ordovician Sarbach formation. 



DiSCONFORMITY 



Mount Wilson Quartzite 



I. Massive-bedded, light gray to white quartzite 24 ^.^ 



This 24 feet {y.2, m.) of quartzitic sandstone repre- 

 sents the 5,000 feet (1,524 m.) in thickness of deposits 

 that occur elsewhere to the southwestward between 

 the Sarbach and the Devonian; also the 285 feet 

 (86.6 m.) in thickness of the dolomite of the Ghost 

 River section (see p. 259). It thickens to 40-50 feet 

 (12.1 to 15.2 m.) east of where the section was taken, 

 and then thins out and disappears on the strike at the 

 top of the high cliff on the south side of the canyon 

 (see pi. 83). 



CANADIAN 

 Sarbach Formation 

 upper .division * 



\a. Gray and purplish-tinted, compact, massive-bedded, 

 lavender-weathering limestone breaking with a con- 

 choidal fracture and on weathering into large blocks 



and a few thin layers 32 9.8 



Purple mottling occurs throughout some of the 

 beds. 



Annelid trails on surface of some layers, and borings 

 more or less scattered through the layers. 

 Dip 35° S. 20° W. (Magnetic). 

 \h. Same as \a except that the color is a more uniform 

 dove tint, with occasional interbedded purplish tinted 

 thin layers. 



At 198 feet (60.4 m.) from top, noted fragments 

 indicating coiled shells (gastropods). 



At 282 feet (85.9 m.) from top, a few cherty 

 nodules occur, and at 312 feet (95.1 m.), stringers and 

 nodules parallel to bedding. 

 Fauna. — At 336 feet (102.4 m-) from top I found gas- 

 tropods (65r). 



* This series of beds should possibly not be referred to the Sarbach, but may 

 be considerably younger. The fauna has not yet been sufficiently studied to 

 permit its being placed into any exact stratigraphic position. Dr. Walcott 

 intended to study these fossils further, particularly since they are not repre- 

 sented in the collections from other localities. — C. E. R. 



