286 WINTHROP P. HAYNES 



top of the massive quartzite layer which forms the rim of the 

 canyon. The strata here strike N. 40 E. and dip 30 west (Fig. 1 1) . 



Massive pink and yellow quartzite (base of Ellis formation ?) 16 feet 



Quartzite and arenaceous limestone in alternating layers 60 



Massive white quartzite, limonite stains 9 



Limestone breccia 2 



Brown arenaceous limestone 62 



Grayish-brown arenaceous limestone and talus 62 



Pink arenaceous limestone in cliff 36 



Yellowish-red arenaceous limestone 47 



Gray limestone in cliffs, shaly at base 10 



Reddish shale 30 



Greenish shale 57 



Buff shaly limestone and talus 100 



Gray bituminous limestone in cliff, with black shale layers 45 



Compact gray and yellowish-brown limestone 24 



Black coaly shale with calcareous bands and gypsum veins 20 



Brown crystalline limestone 4 



Coaly black shale, very fossiliferous 50 



Yellow arenaceous limestone in cliff, some quartzite bands 46 



Red shaly limestone 10 



Total 674 feet 



The fossils collected from the Quadrant formation indicate 

 that it is probably of Lower Pennsylvanian (Pottsville) age. The 

 absence of any strata referable to the Tennesseic suggests the 

 presence of a disconformity between the Madison and Quadrant 

 formations, although no other evidence of such a hiatus was 

 observed by the writer. 



MESOZOIC 



Mesozoic formations are rather poorly exposed in this region 

 and were not studied in detail by the writer. They consist of 

 shaly limestones and sandstones which are generally much less 

 resistant than the Paleozoic limestones and therefore usually 

 occupy lowland areas. These Mesozoic strata border the Missouri 

 Valley on both sides, and the more resistant layers form low ridges 

 which are parallel with the trend of the higher Paleozoic hills. 



