MARGINAL GLACIAL DRAINAGE FEATURES 



543 



east bank have dropped down, leaving a depression now occupied in 

 part by a pond at a level three or four feet below that of the channel 

 bottom. Into this depression and its continuation northward Cathe- 

 rine Creek now flows. It is here that Watson and Fairchild evi- 

 dently placed the outlet of Lake Watkins. 



Obviously there has occurred here a settling-down of a portion 

 of the drift in the central part of the valley since glacial times; cer- 



FiG. 8. — Watkins Lake outlet. Looking up-stream from a point one mile below 

 the beginning. The shallow pond in the foreground is caused by the blocking of the 

 channel by an alluvial fan. 



tainly since the waters of glacial lake Watkins ceased flowing through 

 the channel, for had the settling occurred while the stream was still 

 flowing, the depression thus formed would immediately have been 

 filled with gravel. Besides, had the depression existed then as now 

 the lake would have overflowed at this point rather than at a higher 

 level farther north. 



The melting of an ice mass buried beneath glacial gravels is sug- 



