SOME VARIANT CONCLUSIONS IN IOWA GEOLOGY. 
BY J. E. TODD. 
Having been a resident in southwestern Iowa for many years and 
conversant with several localities in the state of geological interest, the 
writer has naturally followed closely the publications of the present 
Survey treating of them. 
In casting about for a subject for some different conclusions which 
had come to his mind, he thought first of “corrections and additions”, 
but as that savored rather of too much self-assurance the milder form 
was preferred. Since the writer does not arrogate ’superior knowledge 
in the cases, he would simply state his views and leave them to what- 
ever acceptance they may deserve. 
•1. The first variant conclusion concerns a folding of Carboniferous 
rocks in Fremont county: 
Prof. Udden, in his admirable report, has fallen into the same error 
as Dr. White did more than 30 years before. The writer was in the reg- 
ion a few years before he discovered the mistake. It was finally made 
perfectly clear by a visit to the west side of the Missouri river at Jones 
Point, just above the mouth of the Weeping Water. There is a fine 
exposure there which seems to have escaped Meek and Hayden. It shows 
a dip of 4" or 5° SSE. which carries over 100 feet of strata, which are 
exposed in the summit of an anticlinal about a mile north, entirely below' 
the level of the river, in less than that distance. Taking the direction 
from that point to the break in the strata south of Wilson’s quarry per- 
haps half a mile, near the south line of section 23, T. 70, R. 43, we find 
the axis of the told is N. 60° E. 
The fold is so sharp that the heavy limestone strata and nearly the 
w'hole of White’s section at Wilson’s quarry, or Udden’s X, XI, and XII, 
passes entirely out of sight before the south line of section 26 is reached. 
At Nebraska City a section corresponding somewhat to XIX has been 
noted by many and Meek gives a record of Croxton’s boring (Hayden’s 
Final Report of Neb. p. 105) to a depth of 344 feet starting 13 feet above 
high water mark. By a comparison of exposed sections with the record 
of the boring, it seems fairly clear that the top of the sandstone exposed 
in the bottom of Wilson’s quarry and also in the large quarry opposite 
Haney’s, (Udden’s sections X and V, though he fails to -’report this at 
either point) is at the depth of 238 feet or 210 feet below' low water of 
the river there. This sandstone is what White called the base of the 
Upper Carboniferous. The sandstone which he records as exposed at 
Plum Hollow (.Thurman now) and at Hamburg is not the same, but is 
probably that exposed at Wyoming, Nebraska, and Nebraska City, though 
( 183 ) 
