LOESS IN THE WISCONSIN DRIET FORMATION 933 



unlike loess. It is sometimes capped by several feet of heavy 

 clay, which is clearly not the product of loam-weathering. 

 Calcareous concretions occur but rarely, as also those of iron 

 oxide. Shells were not seen. The loess, and especially the 

 associated and genetically equivalent clay, contains an occasional 

 stone of considerable size. The loess, and the clay which goes 

 with it, have a maximum thickness of not less than fifteen feet. 



There seems to be adequate reason for believing that the loess 

 on the outside of the moraine (toward the lake), was accumu- 

 lated in the expanded lake which occupied the site of the pres- 

 ent lake and its surroundings at the time of ice occupancy. 

 There is independent evidence that the lake stood at least sixty- 

 five feet above its present level. This evidence is found in the 

 presence of what appear to be berg-floated bowlders, up to this 

 height about the borders of the depression (then a bay) at the 

 southwest corner of the lake. 



The loess on the inner slope of the moraine doubtless settled 

 out of water which stood there after the ice had withdrawn a 

 short distance to the east. 



Loess at Ablemajts. — Ablemans is about eight miles west of the 

 moraine of the Wisconsin epoch, and in an area not overspread 

 by the ice of any earlier epoch. Here at the extensive sand- 

 stone quarries, there is a fine exposure of loess not less than 

 twenty feet in thickness. It occurs at a rather low altitude, and 

 in such topographic relations as to bring it into unmistakable con- 

 nection with the broad lacustrine (now terrace) flat which occu- 

 pies the valley of the Baraboo, from Baraboo to Ablemans. The 

 exposure is in a ravine, tributary to the Baraboo, and but a few 

 rods from it. The lacustrine flat with which this loess is to be 

 correlated is generally made up, superficially at least, of lami- 

 nated calcareous clay, very unlike loess. It is to be especially 

 noted that the loess at Ablemans does not occur next the 

 moraine, but eight miles away in a small tributary ravine, the 

 head of which did not receive glacial drainage, and that much 

 finer deposits (clay) occur in the main valley between the loess 

 and the moraine where the water was discharged from the ice 



