THE BARITE DEPOSITS OF MISSOURI 41 



distortions of the beds developed during their consolidation. 

 They are rarely more than 40 or 50 feet in length. The Potosi 

 dolomite exposed along Mine a Breton and Mineral Fork shows 

 such undulations well. Probably some of these minor deforma- 

 tions are due to solution, followed by a settling of the beds above. 



(b) Major folds. — There is really but one important fold 

 in the area and that is slight in comparison to the folds in many 

 regions. This is an anticline which extends from the Richwoods 

 region to the southeastern part of the area near Kingston, where 

 it apparently turns eastward and follows, rudely, the course of 

 Big River, In the Fertile region many faults complicate the 

 problem, but the major tendencies in the deformation are still 

 evident. 



The dip of the beds on the west side of the anticline in the 

 Richwoods area is rarely 3 degrees, but it is sufficient to bring 

 the Potosi formation high enough so that it is exposed by ero- 

 sion east of Richwoods. The dip of the beds to the east is prob- 

 ably similar, altho evidence of the eastward dip was found in 

 only one locality. That was on Calico Creek near Fletcher, 

 where the dip is 2 to 3 degrees. 



The axis of the anticline begins about a mile west of the 

 northeastern corner of Washington County, and follows a course 

 about 23 degrees east of south to a point near Kingston where 

 faults replace it. Extending slightly to the south of east is a 

 poorly defined anticline which may be a continuation of the 

 above, but appears to be a separate fold. On Maddis Creek the 

 Elvins formation dips 4° S., 15° W. As a result the bluff on the 

 opposite side of Big River consists almost entirely of the Elvins 

 formation. Farther northeast near Vineland on the Iron Moun- 

 tain Railroad there is a sharp downward fold to the northeast. 

 Whether this is the northern side of the anticline is not known, 

 but such appears to be the case. These two folds appear to in- 

 tersect and end near Kingston, for the rocks to the west and 

 those to the southeast do not show evidence of deformation. The 

 Richwoods anticline is the direct cause of the mining of barite in 

 that region, as it made possible the exposure of the Potosi dolo- 

 mite, and, to a certain extent, the Proctor dolomite, the two for- 

 mations which are economically important in the district. The 



