26-i ASHLEY — GEOLOGY OF ARKANSAS. [May 13, 



Through the centre of 5 S., 21 and 22 W., runs a belt about two 

 and one-half miles broad in which the strata are nearly horizontal, 

 the dip varying from 0° to 25° a little east of south. 



De Roche Creek Anticline. — In 5 S., 20 W., the De Roche creek 

 anticline is crossed by the Arkadelphia-Hot Springs road in the 

 centre of the northeast quarter of section 36. Haifa mile further 

 west, where the axis is crossed by De Roche creek, Mr. Branner 

 found it well exposed in the bank of the creek. The belt of north 

 dips, a mile broad here, becomes narrow to the west until, as it 

 enters 5 S., 21 W., it is less than a quarter of a mile broad, the 

 axis being crossed by Big Hill creek half a mile from its mouth. It 

 is crossed by the Caddo a mile west, in the northeast quarter of 

 section 35, the strike being deflected a little south of west. It has 

 not been identified further west. 



The connection of the axis exposed on De Roche creek with 

 that on Big Hill creek may be strongly questioned, even though the 

 evidence obtained points that way. Theoretically it would be 

 more satisfactory to connect it with the Big Hill creek anticline 

 next described. 



Big Hill Creek Anticline. — Just at the mouth of Big Hill creek in 

 5 S., 21 W., section 36, a ridge (140') juts boldly out, the rock show- 

 ing a dip of Z^° S. As an anticline crosses the Caddo a mile west 

 of this point in section 35, in the same strike, it is probable that 

 the high ridge is in the axis of an overturn. This ridge is con- 

 tinued west of the mouth of Big Hill creek, forming a narrow di- 

 vide between the Caddo and Big Hill creek which here runs east 

 and parallel to the Caddo a quarter of a mile before running into 

 it. The south side of this divide is for some distance composed al- 

 most entirely of a ^^^^ bedding surfaces having a dip of 78° S., 2° 

 W. For a mile or two north of where this anticline is crossed by 

 the Caddo the structure is not clear, the dip varying rapidly ; evi- 

 dences of a fault are abundant, but the amount of throw could not 

 be determined. 



Caddo River Anticline. — The Caddo river anticline is thought to 

 start in an anticline near the Ouachita river, a little south of the 

 centre of 5 S., 18 W., which is crossed by the military road east of 

 the centre of section 29. 



In 5 S., 19 W., an overturn which has been assumed to be on 

 the same anticlinal axis shows nicely on Waterhole branch, a tribu- 

 tary of De Roche creek, in the southern part of section 34. The 



