702 J. L. TILTON STRATA NEAR STUART, IOWA 



interpretation of which the facts presented in this paper are necessary. 

 Finally, the recognition of the strata to the north, to the west, and to the 

 southwest of Stuart as of the Des Moines stage instead of the Missouri 

 stage necessitates a pronounced change in the geological map of Iowa for 

 this region. 22 



22 See accompanying map and sections. The outline of the eastern margin of the Da- 

 kota sandstone is as given in the reports on the geology of Guthrie and Adair counties 

 in the Iowa Geological Survey, vol. vii and xvii, and the exact position of the fault here 

 given from data secured in the summer of 1921 corrects the location of the fault as 

 given in the map of Adair County (idem, vol. xxvii). When the map of Adair County 

 was prepared the outcrops in Jefferson and Grove townships were supposed to be of 

 strata in the Missouri stage. It is now found that they are in the Des Moines stage 

 (Henrietta). 



