352 DRAKE — THE GEOLOGY OF INDIAN TERRITORY. [Sept. 3, 



Fayetteville Shale. 



The Fayetteville shale is probably the stratigraphic equivalent of 

 the AVarsaw division, as recognized in Illinois, Iowa, etc. 



Sees, a-k, PI. V, show the variation in thickness and the associ- 

 ated strata of the Fayetteville shale along its line of outcrop through 

 the Indian Territory. These sections were made at the following 

 localities : 



Sec. a — About two miles west and southwest of Stillwell. 



Sec. b — Four or five miles east-southeast from Wauhillau and 

 one and a half miles south of the Evansville-Tahlequah road. 



Sec. c — Compiled from sections made northwest of Marble and 

 southwest of Bunch. 



Sec. d — West side of Big Vian creek about one and a half miles 

 northwest of Vian. 



Sec. e — Compiled from outcrops along the Illinois river and 

 Greenleaf creek, about five miles east-southeast from Greenleaf. 



Sec. f — About one mile north of Fourteen Mile creek and one 

 and a half miles northeast of Grand river. 



Sec. g — About two and a half miles south-southwest of Mark- 

 hain's store or thirteen miles south of Brushtopped mountain. 



Sec. h — One and a half miles east of Grand river, opposite Ned 

 Adair's ferry, east of Chouteau. 



Sec. i — Brushtopped mountain, a small hill one mile north of 

 Pryor creek and one and a half miles west of Grand river. 



Sec. j — South side of Rock creek about four miles west of its 

 mouth northeast of Adair. 



Sec. k — Along and south of Little Log Cabin creek one and a 

 half miles south of Vinita. 



The Fayetteville shale is a black, friable, clay shale, which 

 usually contains clay-ironstone concretions, and has an average 

 thickness of about fifty feet. This shale immediately overlies the 

 upper Boone limestone, and varies but little around the southern 

 and the southwestern border of that limestone, and also along the 

 western border as far north as the Grand river east of Chouteau. 

 Farther to the northward it is more arenaceous and thinner and 

 varies in color from gray to blue and yellowish. It is doubtful 

 whether there are any outcrops as far north as the Indian Territory- 

 Kansas line that may be referred to this shale. The shale is di- 

 vided throughout by a bed of light blue, friable, fine-grained lime- 



