1 8 COLORADO COLLEGE STUDIES. 



county, west of south from Windoni, is provisionally 

 referred to the Wellington formation. 



THE CIMARRON SERIES. 



With the Wellington formation, ends the Big Blue, lower, 

 or limestone-bearing, series of the Permian. Succeeding it 

 without break, but possibly with a gradually introduced an- 

 gular unconformity, are the Harper sandstones and higher 

 prevailingly red formations that comprise the remainder of 

 the Kansas Permian, and constitute the Cimarron series, 

 which, for Kansas, is nearly the same as the "red beds."* 



So far as known, the series is destitute of any trace of 

 organic remains. 



THE SALT FORK DIVISION. 



The Salt Fork division is so named because all of its 

 formations are found within the drainage-basin of the Salt 

 fork. It includes the Harper, Salt Plain, Cedar Hills, 

 Flower-pot, and Cave Creek formations, and has a maxi- 

 mum thickness of about i,ooo feet. 



THE HARPER SANDSTONES. 



These constitute the lowest and thickest formation of 

 the Cimarron series. They comprise several hundred feet 

 of more or less mottled, but prevailingly dull-red, or brown- 

 ish-red, argillaceous and arenaceous shales and sandstones, 

 above the Wellington shales and below the Salt Plain 

 measures. The word, sandstones, as appUed to this for- 

 mation, is intended to imply, . not that its rocks consist 

 mainly of sandstone throughout their thickness, but that the 

 frequent low ledges of rock which accentuate the forma- 

 tion are of sandstone. Much of the latter is of the sort 

 quarried at Harper — a reddish-brown or roan-colored sand- 

 stone, sometimes mottled and streaked, soft enough to be 

 easily quarried and dressed, but becoming harder by seas- 



*Some authors, however, may have included the limestone-bear- 

 ing Wellington and possibly even the rock-salt-bearing Geuda in their 

 use of the term "red-beds,'' as applied to Kansas rocks 



