STRATIGRAPHIC SUMMARY. 655 



Kingsbury conglomerate 2,000 ft. + 



Piney formation 2,000 ft. + 



Middle Cretacic. 

 montanan. 



Parkman sandstone 300 ft. + 



Pierre shale 3>500 ft. 



Lower Cretacic or Coloradoan. 



Colorado shales, mostly shales including the Mowry 

 and other sandstone formations — Niobrara and 

 Benton not separable (2,200 ft. maximum). 



Cloverly formation (in part perhaps Comanchic) 

 resting disconformably upon the Morrison. 



In Texas marine beds of Coloradoan age but somewhat older 

 than those of the Rocky Mountains constitute the Eagle Ford 

 formation. The lower Benton series is known in Colorado as the 

 Graneros shales, often non-marine, which is succeeded by the 

 marine Greenhorn limestone and the succeeding Carlisle shales and 

 sands, also marine. The Niobrara limestone series (divisible into 

 an upper series of shales, the Apishapa, and a lower limestone, the 

 Timpas) is represented in Texas by the Austin chalk, while the 

 Pierre beds and the Fox Hills are represented in part at least by 

 the Taylor marls. These latter are succeeded in Texas by the 

 Eagle Pass or Navarro formation which probably represents to 

 some extent the marine equivalent of the Laramie. 



In the Rio-Grande Valley of New Mexico, the Cretacic is divided 

 in descending order into: (4) the Galisteo group (2,000 ft. or more 

 of yellow and red sandstones and conglomerates), (3) the Madrid 

 group (2,000 zh ft. of coal-bearing sandstone and shale), (2) the 

 Pierre and (i) the Coloradoan.'^^ 



On the Atlantic coast of North America, the following sub- 

 divisions are recognized: 



SUPERFORMATION. 



Shark River beds — Eocenic. 

 Upper Cretacic or Jerseyan. 

 Manasquan. 



*^ Johnson, D. W., Sch. Mines Quart., 24, p. 36, 1903. 



