70 PLEISTOCENE OF INDIANA AND MICHIGAN. 



extent occur in the valleys of this county and have been penetrated by wells to depths of about 

 100 feet before entering rock. These deposits along White River may be, in part, of Wisconsin 

 age, but on some of the tributaries of the river they are known to be outside the limits of the 

 Wisconsin sheet. In this connection it may be remarked that valleys in northern Monroe and 

 Brown counties which are outside the limits of the Wisconsin outwash carry deposits of gravel 

 and sand, which, in the several forks of Salt and Bean Blossom creeks, form terraces lying 30 

 feet or more above the streams. In these valleys, as in the gulches of central and southern 

 Morgan County, gold and a few diamonds have been found. 



The gravel knolls of Johnson County, like those of eastern Morgan County, are in part 

 within the limits of the Wisconsin drift and may be of pre- Wisconsin age, for the drift in them 

 has a more weathered appearance than that of the surrounding deposits of Wisconsin age. 



The Mount Auburn Ridge in southwestern Shelby County, as already indicated, is very 

 largely of pre- Wisconsin drift. It has been penetrated by a few deep borings which show that 

 the rock surface is considerably below its base. A well at the Mount Auburn schoolhouse, 198 

 feet deep, did not strike rock, passing largely through gravel, parts of which are cemented 

 into conglomerate. Glacial conglomerate outcrops on the slopes of the ridge about a mile south 

 of Mount Auburn. Collett reported that a well 1 mile west of Mount Auburn, on ground fully 

 100 feet lower than the village, struck rock at 108 feet. The following beds were penetrated: 1 



Record of well on Collins farm, 1 mile ivest of Mount Auburn, Ind. 



Feet. 



Soil 4 



Clay, yellow 6 



Clay, sandy 10 



Clay, bowlder 80 



Sand, white - 1 



Sand and gravel 7 



Limestone. 



108 



In Bartholomew County only the western edge lies outside the Wisconsin drift. Most of 

 the surface is rugged, being a continuation of that in Brown County, with only a scanty coating 

 of drift. There is, however, a narrow strip of lowland west of the East White Valley in which 

 the drift has considerable depth. 



Exposures west of Columbus along small tributaries of East White River show 50 feet of 

 yellow till above blue till. Fifty-five feet of yellow pebbly clay and 5 feet of blue waxy clay 

 above Devonian shale was found in a well on the farm of H. C. Harris, 1 mile west of Taylor- 

 ville, very near the border of the Wisconsin drift; the greater part of the drift is thought to 

 belong to the earlier ice invasion. 



In the northeast part of Seymour, Jackson County, a gas boring passed through a black 

 muck, apparently an old flood plain of East White River, at a depth of 55 to 65 feet, and other 

 borings in the vicinity found the black muck at similar depths. No typical till appears to be 

 present, the entire series of beds being water deposited. 



Pleistocene beds penetrated in gas well at Seymour, Ind. 



Feet. 



Sand, coarse 12 



Sand or silt, very fine, almost a clay 43 



Muck, black 10 



Sand, coarse, with large amount of water 5 



Clay, blue , - 5 



75 

 i Collett, John, Eleventh Ann. Rept. Indiana Dept. Geology and Nat. Hist., 1881, p. 68. 



