378 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



a divide, the waters from the northeast part of the apron flowing north- 

 ward to enter the Great Miami near Alexandersville, while that from the 

 southwestern part flows southwestward along the outer border of the 

 moraine, entering the Great Miami near Franklin. On Isaac Miller's farm 

 a well on this apron penetrated gravel of medium coarseness to a depth 

 of 17 feet, where water was obtained. It is Mr. Miller's opinion that the 

 gravelly phase of this outwash apron does not extend much beyond his 

 farm, but that the remainder of the plain is underlain by clay or silt, 

 and has a black mucky soil. The gravelly portion of the apron has a red 

 loamy soil. 



On the uplands between the Great Miami and Sevenmile Creek there 

 is also a small outwash apron. It covers 2 or 3 square miles in the vicinity 

 of West Elkton. Its altitude is about 200 feet above Sevenmile Creek and 

 still more above the Great Miami Valley. It occupies a part of the divide 

 between these streams, its eastern portion draining southeast to the Great 

 Miami below Middletown, while its western portion drains to Sevenmile 

 Creek near Collinsville. Exposures near the border of the moraine show 

 well-rounded clean gravel of medium coarseness, which has a variable 

 thickness, owing to the irregularities of the substrata, but its own surface is 

 quite smooth. 



The valley of Sevenmile Creek contains gravel terraces whicli are 

 thought to be of the age of the outer member of this morainic S3^stem, but 

 the coimection was not clearly worked out. The vallej^ of this creek con- 

 tains till as well as gravel below the point where the moraine crosses, the 

 till being capped by a coating of gravel several feet in thickness. Above 

 the point where the outer member crosses there is far less gravel than 

 below, the outwash from the later members being chiefly sand or silt. This 

 valley has been deepened but little since the gravel terraces were formed, 

 their surfaces throughout much of the lower part of the valley being only 

 30 or 40 feet above the present stream, while the bluffs bordering the 

 glacial terrace rise to a height of 200 feet or more above it. 



On the uplands west of Sevenmile Creek there is, in the vicinity of 

 the State line, an extensive till plain just outside the outer member of this 

 morainic system, whose surface on the border of the moraine is capped by 

 a silt deposit 1 or 2 feet in thickness which appears to be a morainic out- 

 wash. The extent of the silt deposit was not determined, though it is 



