MOSKOE COUNTY. 279 



Kinderltook Group. This group also owes its outcrop in this county 

 to the disturbing influences by which the Trenton limestone has been 

 lifted above the surface at Salt Lick Point, and, in the absence of the 

 Devonian and Upper Silurian groups, the shales and chocolate-colored 

 limestones of which this group consists immediately overlie the Trenton 

 limestone, as indicated in the foregoing section. The lower portion of 

 the group consists of ashen-gray shales, which pass upward into choco- 

 late-colored shales and limestones, and these form the slope at Salt Lick 

 Point between the two escarpments of limestone, the Burlington above 

 and the Trenton beneath. A few fossils were obtained here, mostly 

 from the chocolate-colored shales and slialy limestones, among which 

 were Frodnctus BurUmjtonemis. frpirifer (Irimcvi, or a closely allied 

 species. Kpiri/<r Vfnutnense, /Xpir it/era Hannibalensis, Paleacis enorme, 

 Aclinufrinu* pixtiUiformix. Strophomena analoya, Conocarflium and Za- 

 phrcntis of undetermined species. This group overlies, unconformably, 

 the outcrop of Trenton limestone at this point, and dips rapidly beneath 

 the surface in either direction. 



Trenton Liiuextone. This is the oldest or lowest formation that ap- 

 pears above the surface in Southern Illinois, and it only outcrops at one 

 other point, in Alexander county, where, as here, it forms the nucleus 

 of an anticlinal axis. The first appearance of this limestone in this 

 county, in. tracing the river bluff southward, is about two miles below 

 JEagle Cliff, where it forms a low ledge of massive gray limestone at the 

 base of the bluff, a short distance below the point where the main road 

 from AVaterloo to Harrison ville enters the river bottom. From this 

 point it rises rapidly to the southward, and a half-mile below where it 

 first makes its appearance it forms a perpendicular cliff nearly a hun- 

 dred feet in bight, which forms the culminating point of the axis. There 

 appears to have been a dislocation and down-throw of the strata at this 

 point, for below the valley of a small creek which intersects the bluffs 

 on the lower side of Salt Lick Point the lower portion of the bluff is 

 formed by an outcrop of Burlington limestone, the Trenton limestone 

 and the Kinderhook group having both been carried down below the 

 surface, and the beds dip rapidly to the southward, or in the opposite 

 direction to the beds at Salt Lick Point. The point where the disloca- 

 tion of the strata occurs is now occupied by the creek valley, and con- 

 sequently the amount of the down-throw could not be accurately deter- 

 mined from the poor exposure of the beds; but I inferred that the 

 amount could not be less than two hundred feet, as neither the Trenton 

 nor Kinderhook groups were to be seen on the southern slope of the 

 axis. 



That portion of the Trenton limestone outcropping in this county 

 consists, for the most part, of heavy-bedded, yellowish-gray crystaline 



