COKKELATIVES OF BLOOMINGTON MORAINIC SYSTEM. 121 



SUGAR CREEK BASIN. 



There is a plane-surfaced gravelly district immediately northeast of Crawfordsville whose 

 relation to the moraine is not clear. It heads just outside a weak moraine which crosses Sugar 

 Creek at Garfield, and may be, in part at least, the outwash from that moraine. The gravel 

 continues westward along Sugar Creek valley past Crawfordsville, but has been terraced by 

 Sugar Creek, the main terrace being about 20 feet below the uneroded tract east of the city. 



WABASH RIVER BASIN. 



The Wabash seems to have furnished a channel for vigorous discharge throughout the devel- 

 opment of the Bloonhngton morainic system. The gravel plain just west of Williamsport heads 

 in a recess in the outer member. The great Wea gravel plain of western Tippecanoe County, 

 which is about 4 miles wide (including the valley of Wabash River cut in it) and 9 miles long, 

 and which fills the interval between Lafayette and the west line of the county, seems to have 

 been developed during the recession of the ice across the district it covers. Its highest and 

 oldest part is a strip on its south side less than a mile wide and about 3 miles long, which lies 

 about 650 feet above sea level or 150 feet above Wabash River just east of West Point. Its 

 altitude is about 630 feet at the east end and falls to about 615 feet 6 miles to the west, opposite 

 West Point. The material is a fine sandy gravel such as would be expected in a broad plain 

 with a slope of only 15 feet in 6 miles. 



INNER BORDER. 



From the slope, and altitude of the surface the southern tributaries of White River would 

 be expected to run northward to that stream, but they do so only from near Muncie eastward. 

 West of Muncie the streams south of White River run nearly parallel with it. Fall Creek, the 

 largest tributary, flows westward down a slope more gradual than that to the north. Lick 

 Creek, the main tributary of Fall Creek, runs west entirely across Madison County only 2 to 

 5 miles from FaU Creek and at markedly higher level. Farther south in northern Hancock 

 County the headwater portion of Sugar Creek runs west for 10 mUes and then turns south 

 through a depression in the great drift belt. The westward course of these streams may not 

 be difficult to explain, the ice sheet in its lingering withdrawal probably causing the develop- 

 ment of streams along its front which persisted after the ice had melted off. No clearly 

 defined moraines along the north side of these west-flowing streams demonstrate this relation 

 to the ice sheet, but the halts may have been too brief for their development. The westward 

 course of the headwater part of White River is not remarkable, for it is in the line of as rapid 

 fall as could have been selected. In Howard, Clinton, Carroll, and Cass counties the prevailing 

 course of drainage is westward down a slope a little more gradual than that northwestward 

 and directly toward the Wabash Valley, and here also it seems probable that the streams were 

 westward along the south edge of the retreating ice, though definite moraines are not present 

 fully to demonstrate this relationship. 



In general the west-flowing streams of this region have cut narrow valleys, which deepen 

 toward their mouths and are bordered by abrupt bluffs that stand about at the level of their 

 border plains, but the west-flowing part of White River presents an interesting exception in 

 part of its course. The valley deepens in the usual manner from its headwaters westward to 

 the vicinity of Anderson, where it reaches a depth of 70 or 80 feet. West from Anderson the 

 bluffs become less abrupt and soon drop to 30 feet or less, though within a mile or two back 

 from the stream an altitude of 75 to 100 feet above the river is reached. The slopes are 

 undulatory and some of the swells appear to have been built up by the ice sheet rather than 

 left as a result of drainage erosion. It seems probable that this part of the valley was left as 

 a depression and was only partly filled by drift deposits of the Wisconsin invasion. 



Some of the northern tributaries of White River, notably Killbuck Creek, Pipe Creek, and 

 Duck Creek, have valleys with broad undulatory slopes similar to the part of White River 

 valley west of Anderson. Well-defined knolls on the slopes are thought to have been formed 



