282 ASHLEY — rxEOLOGY OF ARKANSAS. [May i;5, 



the Cossatot westward the shales which are exposed on the Cossatot 

 have been eroded, producing in 5 S., 31 W., the Prior creek valley. 

 This anticline, if produced into 5 S., 32 W., will join with the 

 South mountain anticline. 



Minor Anticlines. — In 5 S., 29 W., a small anticline is crossed 

 by Harris Fork in section 15, the southeast quarter. In 5 S., 



30 W., parallel outcrops of the thin novaculite seem to indicate an 

 anticline or overturn in section 17, northeast quarter. In 5 S., 

 32 W., section 16, northwest quarter, two small anticlines are cut 

 by Cross creek. ^ 



Baker Spring Ridge Ajiticline. — In 5 S., 27 W., the Little Mis- 

 souri river crosses an anticline in the northwest quarter of section 

 16. This anticline runs a little south of west, forming a two hun- 

 dred foot ridge between Clover creek and James creek. In 5 S., 

 28 W., it is crossed by the Saline in the southeast corner of section 

 16; from this point it runs due west, being crossed by Harris Fork 

 in 5 S., 29 W., section 15, in the southeast corner. On the south 

 side of the anticline, between Harris Fork and Moore's creek, is a 

 two hundred to two hundred and fifty foot ridge, highest at the 

 Harris Fork end. It passes south of Baker Spring in 5 S., 20 W., 

 section 14, southeast corner, and where cut by Baker creek, in sec- 

 tion 15, southeast corner, there is one of the best exposures of an 

 anticline in the whole area. 



Going west the ridge made by this fold rises to a height of two 

 hundred to two hundred and fifty feet. It is crossed by the Cossa- 

 tot in the southeast quarter of section 17. In the centre of section 

 17 is the fine exposure known as the Falls of the Cossatot. The 

 topographic effect of these heavy ledges is seen in the long high 

 ridge between Prior creek and Cow creek, which runs across 5 S., 



31 W. In the southeast quarter of section 14 and in the same strike 

 to the east, shales are exposed structurally identical with the shales 

 just under the heavy novaculite exposed in the Prairie mountain 

 anticline on the Little Missouri river. Baker Sulphur Springs issue 

 from this shale. 



West of the Cossatot Mr. Means found this anticlinal axis in 

 5 S., 32 W., section 13, southeast quarter. 



Mill-site Branch Anticli?te. — In 5 S., 27 and 28 W., the Mill- 

 site branch anticline was not surely found, but the presence of thin- 

 bedded novaculite shales, horizontal dips and the topography sug- 



1 All structures on Cross creek were worked out by Prof. A. H. Purdue. 



