178 University Geological Survey of Kansas. 
Iola quadrangle, the dip-plain is practically uniform to Iola, 
where the elevation of the upper surface of the limestone is 
about 90 feet, making a dip of 140 feet in twelve miles. 
Throughout this distance the overlying shale-bed is almost en- 
tirely removed, but not with sufficient completeness to expose 
the limestone all of the way. It is difficult to believe that 
there is any form of an anticlinal arch here trending north- 
east and southwest. : 
Five miles to the north of Iola is the little town of Carlyle, 
situated on Deer creek, a stream flowing southwest. This 
creek certainly lies in a synclinal trough. On the northwest 
side the rocks rise to the north and northwest, while on the 
east they rise likewise. In fact, here is one of the highest 
angles of dip known in the state, where the Allen limestone 
rises from the bed of Deer creek southeastward. This syn- 
cline seems to follow down Deer creek to the Neosho river 
and down the Neosho river to below Chanute. In this way, 
therefore, there is a rising of the rocks both eastward and 
westward from the Neosho river and Deer creek troughs. The 
strong gas-wells of Iola, it is true, lie east of this synclinal 
trough. But as the rocks continue to rise eastward to Moran 
one would expect to find strong gas extending that far, with 
a better supply of it in the vicinity of Moran than at any 
intermediate point, provided an upward-sloping inclination of 
bedding-plains would produce it. 
Here, therefore, we must conclude that structural condi- 
tions have but little, if anything, to do with the great Iola 
gas-field, and must look for the explanation of its existence 
to some other particular geologic conditions. It would seem 
that the explanation is found, in part at least, in the character 
of the sandrock 900 feet below the surface rather than in any 
structural conditions which may have existed. 
No small amount of labor has been expended in investigating 
this subject. A study of the seven county maps herein in- 
cluded will reveal the fact that our oil-fields and gas-fields are 
scattered here and there with apparent irregularity through- 
out the territory. We have been unable thus far to connect 
them with structural conditions to a sufficient extent to jus- 
tify the general conclusion that structural conditions alone 
control the presence of oil or gas. The comparatively rich 
oil-wells in the Neosho river valley just mentioned certainly 
are in a synclinal trough; and, likewise, the gas-wells in the 
