434 THE ILLINOIS GLACIAL LOBE. 



of the upper beach. In all probability it was deposited by wind, for it 

 reaches in places an elevation 125 feet above the lake, or about 60 feet 

 above the upper beach. It has a range also of fully 60 feet in its elevation. 



While the beach was forming along the inner face of Covert Ridge in 

 southern Berrien County, Michigan, there were probably bays or marshes 

 occupying the low land back of the ridge, for this in places scarcely rises 

 to the level of the beach. An examination of the plains drained by Galien 

 River brings to light only a slight sand coating and little, if any, evidence 

 of wave cutting. The greater part of the plain stands so near the level of 

 the upper beach that there were probably only marshes at the highest lake 

 stage. The sand may have been deposited by wind or perhaps by a small 

 lake held between the ice border and the Valparaiso morainic system. In 

 a plain between the outer till ridge and the Valparaiso system near the 

 village of Baroda, there appears to be slight wave cutting-, both on the 

 border next to the Valparaiso system and the east border of the outer till 

 ridge at an elevation nearly 20 feet above the level of the upper beach as 

 developed on the inner slope of Covert Ridge. There are also conspicuous 

 deposits of sand to a height of 10 feet above that beach, or about 70 feet 

 above Lake Michigan. This determination led the writer to make exam- 

 inations along the base of the Valparaiso system farther north and also of 

 the borders of the till ridges toward the north and west with a view to fixing 

 the highest limit of wave action and ascertaining, if possible, whether the 

 greater height of wave action on this plain is due to a small lake held between 

 the ice front and the Valparaiso system, or to a stage of Lake Chicago some- 

 what higher than the supposed upper beach on the slope of Covert Ridge. 



An extensive gravelly plain, apparently a delta, is found back of Covert 

 Ridge on the border of the St. Joseph River. The greater part of this delta 

 stands 50 to 60 feet above Lake Michigan, or sufficiently low to be connected 

 with the 60-foot beach of Lake Chicago. In the midst of the Valparaiso 

 morainic system the river is bordered by a gravel terrace which descends 

 from about 100 feet above the lake at Niles to 80 feet at Berrien Springs, 

 and to about 70 feet at the point where it expands into the delta. On 

 the border of this terrace below Berrien Springs, in sees. 1 and 2, T. 6 S , 

 R. 18 W., there are occasional basins 8 or 10 feet in depth, occupying an acre 

 or more each, whose rims stand only about 80 feet above Lake Michigan. 

 These basins apparently stand above the leA T el of the highest stage of Lake 



