BEARING OF FAULT ON POSITION OF COAL 701 



has near Lewis, in Cass County, which parallels the west side of the fault 

 on the upthrow side. 



Bearing oe Fault on Position of Coal and on Lay of Strata to 



the North 



No one has yet traced the fault-plane farther to the northeast than the 

 region described in this paper, but the fault evidently has an important 

 economic bearing on the position and relation of coal north of the fault, 

 as near Panora, Perry, and Boone, to that south of the fault, as at Van 

 Meter, Des Moines, Orolabor, and Enterprise. 



To the northeast, along the general direction of the fault, there are 

 peculiarities in the distribution of the Mississippian, Upper Devonian, 

 and Silurian strata, most of which have been classed as evident discon- 

 formities, but the direction of the fault is certainly suggestive of the 

 possible presence of another factor. It can not at present be affirmed 

 whether or not the fault, or a series of parallel faults, extends into that 

 area, or whether or not the disturbance there becomes a fold. 



Bearing of Fault on Position of Coal West of Stuart 



The relations along the fault make it evident that for some distance 

 west of Stuart there is an area beneath the drift and the Dakota sand- 

 stone that may be expected to bear coal, the amount and extent of which 

 coal can only be ascertained by prospecting. Previously it was thought 

 that the coal mined at the old Eureka mine, in western Adair County, 

 came from a small seam 30 feet below the Hertha limestone ; but we must 

 now recognize that that seam is one of those deep down in the Des Moines 

 stage, related to those below the Appanoose beds in the southeastern part 

 of the State. 



Effect on the Interpretation of deep Well Eecords, and 

 Geological Map of Iowa 



Up to the present time the apparent absence of distinct Kansas City 

 strata in the deep well at Atlantic 20 has seemed strange. . Now the sig- 

 nificance of the apparent absence is clear. There are no Kansas City beds 

 in that part of the State. 21 At Stuart there is a deep well, to the correct 



20 W. H. Norton : Underground water resources of Iowa. Iowa Geological Survey, vol. 

 xxi, p. 1121. 



John L. Tilton : Geology of Cass County. Idem, vol. xxvii, p. 257. 



21 This statement is in part dependent on evidence that the Kansas City stage is lack- 

 ing farther west in Iowa — a point discussed in a paper on The Carboniferous strata of 

 the Missouri Stage in Southwestern Iowa, accompanied by sections and a map of the 

 surface distribution of the subdivisions of the Missouri stage, by the present writer. 

 This paper is now in the possession of the Iowa Geological Survey. 



