362 TIIE GEOLOGY OF MINNESOTA. 



[Hudson River and Galenx 



a light-colored, crumbling calcareous shale or clay which may belong to 

 the Hudson River epoch. No fossils have been found in it. It has more 

 resemblance, lithologically. to some Cretaceous beds,*, but it holds, 

 geographically, the right position to fall within the shale seen at 

 High Forest in Olmsted county. This differs from that, however, in not 

 being so coarse, nor in any degree arenaceous. The points referred to are 

 both in the northeastern corner of the county. Along the road a mile and 

 a half north of Grand Meadow it appears in a weathered and washed slop- 

 ing exposure, near the crossing of the north fork of Bear creek. No other 

 rock is to be seen in the vicinity, and nothing indicates its stratigraphic 

 relation to other strata except that it occupies a position somewhat more 

 elevated than the rock quarried by Mr. Bush, about a mile east of (irand 

 Meadow. An exposure of similar shale is visible in the N. E. \ sec. 11, Ra- 

 cine, by the highway, east of the easterly crossing of Bear creek. This 

 outcrop is topographically lower than the Cretaceous conglomerate seen 

 in the immediate vicinity in the highest land. 



The Galena and Upper Trenton. This limestone strikes across the 

 northeastern corner of the county, and doubtless there are some exposures 

 of it in the banks of the streams in Pleasant Valley and Uacine. but none 

 of them have been seen. 



THE DRIFT. 



It is only in the eastern portion of the county, and mainly in the 

 northeastern, that there is any noticeable deposit of the loess loam. The 

 soil here is somewhat different from that of the rest of the county, being 

 rather lighter, both in color and composition. In general, throughout the 

 county the drift consists of a stony clay, or till. The surface is smooth, or 

 gently undulating. This clfty has a light color for the first ten or fifteen 

 feet, and below that depth it is apt to be blue. Stones of all kinds are dis- 

 seminated through it. Some of the boulders are very large, and consist 

 of granite. Sometimes very large boulders lie on the surface. Several 

 such may be seen near Rose Creek village, and near Adams, and between 

 Adams and Le Roy. At Austin a granite boulder was broken for building 

 stone. It was at least sixteen feet long by twelve feet wide. Others were 



*See the reports on Goodliue and Wabasha countif* 



