MORAINIC SYSTEMS AT HEADS OF LAKE MICHIGAN AND SAGINAW BASINS. 185 



TOPOGRAPHY. 

 ALTITUDE. 



Near the northern end of the interlobate tract, about 10 miles southeast of Cadillac, is the 

 highest point in the southern peninsula of Michigan, the precise location being in sec. 12, Sher- 

 man Township, Osceola County, and the altitude a little more than 1,700 feet above sea level. 

 A tract of only a few square miles of this moraine, mainly in the area just referred to, rises above 

 the 1,500-foot contour; about 50 square miles in the same region rises above the 1,400-foot 

 contour; and but little more than 100 square miles rises above the 1,300-foot contour. A con- 

 siderable portion of the massive belt from Big Rapids northward rises above the 1,000-foot 

 contour, but from Big Rapids southward only the crests of the ridges and a few prominent points 

 reach that altitude. The altitude in the vicinity of Grand Rapids is little more than S00 feet 

 on the crests of the morainic ridges and is only about 700 feet on the lower land between the 

 ridges. At the junction of the outer moraine of the Kalamazoo system and its correlative 

 moraine of the Saginaw lobe southwest of Plastings an altitude of about 1,050 feet is attained. 

 The range in altitude along the line of this interlobate tract is thus about 1,000 feet — from 

 700 feet up to 1,700 feet above sea level. From this interlobate tract there is a general west- 

 ward descent to the Lake Michigan basin and a general eastward descent to the Saginaw basin. 

 (See PL VII.) 



RELIEF. 



The relief of the massive moraine above the border districts is more conspicuous from 

 Mecosta County northward than it is southward. In eastern Newaygo and Lake counties it 

 amounts to about 300 feet above the plains on the west, and in northern Osceola County it is 

 about as much above the plain around Cadillac. On the eastern border north of Muskegon 

 River it is 300 to 500 feet, but south from that stream it scarcely exceeds 100 feet. From 

 the vicinity of Big Rapids southward it is as much as 100 feet in only the most prominent parts 

 of the morainic system. In the southern part of the system it is most conspicuous in western 

 Barry County near the junction of the Kalamazoo system of the Lake Michigan lobe with the 

 same system of the Saginaw lobe, where the crests of the highest ridges stand about 300 feet 

 above the low plain to the west traversed by Gun River. 



CHARACTER. 



The interlobate tract is generally of a pronounced knob and basin type of topography, 

 but it includes gentle swell and sag areas of considerable size. One of the most extensive of 

 these lies south of Grand Rapids, where only a few sharp knolls appear throughout an area of 

 perhaps 100 square miles. The portion of the Kalamazoo morainic system between Grand 

 and Muskegon rivers in northern Kent and western Montcalm counties carries only a few promi- 

 nent ridges and has few knolls that exceed 50 feet in height. A considerable part of the massive 

 moraine in Newaygo, Mecosta, Lake, Osceola, Wexford and Missaukee counties has a very 

 irregular surface with sharp knolls 50 to 100 feet in height, among which are numerous basins. 

 The highest part of the moraine, where an altitude of 1,700 feet above sea level is attained, 

 consists not of sharp knobs but of a massive accumulation covering several square miles and 

 rising like a great dome above the surrounding moraine. The greater part of it has already 

 been brought under cultivation while neighboring lower districts with more broken surface 

 still remain uncultivated. In Barry County, especially southwest of Hastings, the Kalamazoo 

 morainic system is characterized by larger lakes than are commonly found elsewhere along the 

 interlobate tract. Indeed, lakes are not so conspicuous in this interlobate tract as in the one 

 between the Saginaw and Huron-Erie lobes. Small lakes and marshy depressions are, however, 

 very common all through it. 



The interlobate tract includes several small gravel plains which were developed as outwash 

 from one or "both of the ice lobes. They are in places thickly set with basins — conspicuously so 

 as a rule at the border between the gravel plains and the associated moraines. The distribution 



