GLACIAL WATERS IN THE LAKE ERIE BASIN 



73 



advance or retreat of the ice front involved oblique overriding or 

 uncovering of the slope. 



2 Shore lines. The Maumee shore line does not reach into New 

 York, and is said to terminate near Girard, Pa. The Whittlesey 

 beach is a definite and generally simple ridge extending east to near 

 Marilla, or 100 miles farther than the Maumee. The Warren shore 

 comprises a series of multiple ridges or bars as far east as Indian 

 Falls, or 15 miles beyond the Whittlesey. From Indian Falls east 

 it is weaker, broken and simple. 



3 Possible Arkona. The only bars which can be regarded as 

 Arkona are the higher ones of the Warren series. But these are 

 not subdued by drowning; they are stronger than the Whittlesey; 

 they are less interrupted and generally stronger than the lower 

 bars ; and they extend far beyond the limits of the Whittlesey. 



4 Spacing of the beaches. The vertical distance between the 

 Whittlesey and the highest Warren bars is commonly from 45 to 50 

 feet. The only instance of less spacing is southwest of Westfield, 

 where five sections have given records of intervals 35-40 feet. 

 The vertical intervals between the several Warren bars have no 

 steadiness which would indicate distinct lake levels. The total 

 range of the Warren bars is usually 20-25 feet, the greatest 

 ranges being on deltas, and only two exceptional localities giving 

 more than 25 feet. Some of the best sections, apart from deltas, 

 give ranges of 11-15 feet, with interval between Whittlesey and 

 upper Warren of 55-60 feet. The total range of the entire shore 

 features is about 70-75 feet. The Belmore -Arkona interval in 

 Michigan of 30-31 feet does not exist in New York. 



5 Ice border drainage. The glacial drainage followed along the 

 receding ice front, and clearly marks the successive positions of 

 the latter. The streams debouched at the Whittlesey level as far east 

 as the level extends. But beyond the Whittlesey limit, as at Alden, 

 Crittenden, and Fargo, the ice border drainage clearly reached 

 down to the Warren level. 



Applying these facts to the three postulates of ice recession 

 the conclusion is that (A) and (B) are emphatically ruled out, 

 and that (C) applies to the New York area only subsequent to 

 Arkona time. It is not doubted that the recession of the ice front 

 may have been unsteady, even in New York, but the practically 

 continuous recession in New York is in best accord with the dis- 

 covered facts. The Arkona teach does not appear to be repre- 

 sented in New York. The channels and deltas of glacial drainage 

 are clear, definite, unmistakable evidence of the ice limits and of 

 the lake levels. As far east as Marilla the ice border drainage 



