^16 DRAKE — TPIE GEOLOGY OF INDIAN TERRITORY. [Sept. 3, 



is about two feet thick. It is mined to some extent along the 

 Thomas fork of Elk creek, at a place about six miles east of Che- 

 cotah, where it is about fourteen inches thick. Along Elk or Dirty- 

 creek, about four miles east of Checotah, the coal is eighteen to 

 twenty-four inches thick. From Starvilla to Elk creek, and doubt- 

 less much farther, a five to six-inch seam of coal occurs regularly 

 fifty to seventy-five feet above the McAlester bed. These beds in 

 the Choctaw coal field are separated by about one hundred feet 

 of gray clay shale. 



The McAlester coal outcrops six or seven miles southwest of 

 Muscogee, where it is about one foot thick and is worked for local 

 demands. 



Another outcrop was seen four or five miles west of Chelsea, 

 where it was worked at several places for local demands. At the 

 Robinson bank it is eighteen inches thick, and of uniform quality 

 throughout. At the McFadden coal bank the same qualities are 

 shown. 



About a hundred feet above this bed and four miles farther west, 

 a coal bed fifteen inches thick outcrops. It is also worked some- 

 what for local use by stripping. This bed is probably not repre- 

 sented south of the Canadian river, but the outcrops 'along Coal 

 creek, twelve miles east-northeast from Okmulgee, and those five to 

 six miles southwest of Chelsea, are probably the same. On Coal 

 creek the coal is about fifteen inches thick and quite uniformly 

 good. The bed dips i° to 3°, is overlain by carbonaceous clay 

 shale, and underlain by fire clay. Southwest of Chelsea the coal is 

 about ten inches thick and of very good quality. 



Mayberry Coal Bed. — The coals occurring at the top of the 

 Cavaniol group, and that probably represent the northern extension 

 of the Mayberry bed, were seen as follows: 



The upper bed outcrops along Coal creek, twelve miles south of 

 Okmulgee, where it is parted by from four to eight inches of shale 

 and shaly coal. The upper stratum of coal is fourteen inches thick 

 and the lower one is from fourteen to sixteen inches thick. Both 

 strata are apparently good, but iron pyrites is rather common in 

 places through the coal. In general appearance this coal is almost 

 identical with that occurring four or five miles west of Chelsea, and 

 the chemical analyses show them to have the same general proper- 

 ties. The next outcrop of this coal bed was seen along Coal creek, 

 about six miles east of Sapulpa. At that place it is from twenty- 



