GLACIAL WATERS IN THE LAKE ERIE BASIN 25 



south of Eden may have contributed detritus to the sand plains 

 west of North Colhns; while the deltas at Eden and Eden Valley 

 were built by the later drainage south of Hamburg. 



Hamburg to East Aurora [pi. 5]. In this section, lying 

 between Eighteenmile and Gazenovia creeks, the stream phenomena 

 become more complex, as the land slope is not steep and the surface 

 is dissected by large creeks. The maps show the observed channels. 

 The highest channel noted is 4 miles due east of Hamburg, and 

 over 1 100 feet altitude. The lowest channels are apparently 

 connected with Whittlesey lake erosion. 



At the four-corners, 2 J miles east of Armor and 2 miles south of 

 Orchard Park, is a heavy bluff, pictured in plate 12, which is a con- 

 tinuation of the large channel 2 miles southeast of Orchard Park, 

 crossing both the highway and railroad with a southwest direction. 

 The head of this river course is a channel 3 miles west of East 

 Aurora at Longs Corners, on the "Quaker" road, figured in plate 13. 

 It lies just south of the three-corners, with direction nearly east 

 and west; the bluff being 35 to 40 feet high, in rock, and the clear 

 channel 10 to 15 rods wide. The head of this cut lies across the 

 east and west road with a scourway 20 rods wide. The total 

 length of this river channel is something over 5 miles. 



South of East Aurora the slopes are smoothed and broadly 

 terraced by water flo^^^, carrying the overflow of the east branch 

 valley of Gazenovia creek, but the scourways are not definitely 

 mapped. 



The detritus carried by this eastward drainage from the Gaze- 

 novia creek was contributed to the broad delta filling on which 

 Hamburg stands. 



East Aurora to Cowlesville [pi. 5]. This section, extending 

 from Gazenovia creek to Gayuga creek, has a most interesting 

 development of moraine, channels and deltas, and the phenomena 

 are complicated by the change of base level from the Whittlesey 

 to the Warren plane. In all the territory thus far described, 

 lying westward to Pennsylvania, the stream phenomena ended at 

 the Whittlesey level, as that lake water was the receiving body 

 and the base level of drainage. While the ice front was lying in 

 this section the outlet of Lake Whittlesey across the "Thumb" 

 of Michigan was abandoned [see p. 42] and the lake waters were 

 lowered to a new outlet, thus establishing Lake Warren. East of 

 Marilla the lower stream channels are cut down to the Warren plane. 

 Delta fillings at the Whittlesey level occur in this section, but are 

 not found further eastward. 



