HAWOKIH: IHE S TRAIIG R AHPV OF TH K KANSAS COAI, MEASUKKS. 273 



probably they connect with the heavy shale beds at the base of the 

 Coal Measures in Arkansas and Texas, making one continuous form- 

 ation from 600 to 700 miles in extent. 



The Cherokee shales are therefore of much more than local import- 

 ance. This is true not only from the standpoint of stratigraphy, but 

 also on account of their great economic importance. Wherever they 

 are known they carry relatively large bodies of coal, and in Kansas 

 and Missouri they and the included sandstone are the main oil and 

 gas producers. 



Wherever the Cherokee shales are known there is also a s|irinkling 

 of calcareous matter. Tne various drill records of wells in Cherokee 

 and Crawford counties show that limestone forming conditions were 

 approached many times during the formation of the shales. Little 

 beds from four inches up to twelve or fifteen inches in thickness are 

 often met with, but not regularly enough to be regarded in strati- 

 graphy. 



Finally after the 450 feet or more of the Cherokee shale beds, with 

 occasional sandstone beds, had been deposited, the conditions 

 changed and a limestone period was ushered in. The lower of the 

 Oswego limestones, the Fort Scott cement rock, was first formed, then 

 a thin bed of shales, and later the upper Oswego system. These two 

 systems lie so close together they may be regarded as one, for wher- 

 ever one extends the other does also, with the thin shale parting 

 between. Yet from the bituminous nature of the shales we know 

 that during its formation the conditions must have been favorable for 

 plant growth, hence dry land areas, or marshy conditions must have 

 prevailed. 



Above the Oswego limestones lies a bed of shale of variable thick- 

 ness. In places it is over 40 feet, but the borings at Mound Valley 

 and Cherryvale, and all those made north of Thayer, as well as those 

 north of Fort Scott, show that the shale almost entirely disappears, 

 so that the overlying limestone, the Pawnee, really belongs to the 

 same great limestone forming periods with the Oswego systems. The 

 lateral extent of the Pawnee limestone is fully as great as that of the 

 Oswego as far as can be determined by the deep borings and the 

 surface indications. It reaches all the way from Kansas City to 

 Cherryvale and Independence, and probably much farther. In 

 thickness these three systems vary considerably. At Stover, a well 

 record shows the two Oswego limestones to be 24 and '21 feet. The 

 Pawnee in places west of Fort Scott is more than 40 feet thick, while 

 the majority of the drill records show that the three vary from 5 to 20 

 feet each. 



