STREAM-CAPTURE IN MICHIGAN 



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in by tributaries and washed down from the valley sides. A part of 

 the flat valley floor is thus accounted for; that near the head being 

 explained by the fact that there is here no surface stream at all, but 

 little waste has been removed, and the filling of the valley continues 

 without interruption. 



One of the clearest evidences of capture is the remnant of Oak 

 Run valley perched on the Huron bluff and running neatly around 



Fig 4. — Looking down Oak Run from across mouth of Oak Ravine. 



a spur into Oak Ravine. The bench-hke effect which it gives to 

 the bluff is very clearly seen in the field, although it appears but 

 faintly in Fig. 2 because of the distance at which the view was taken. 

 The bluff at the elbow of capture is covered over with tufts of 

 grass and peat sliding down from the channel of Oak Run. Wet- 

 weather gullies are eating farther and farther back, so that the bench 

 will finally disappear. These facts unite with other evidence pre- 

 sented in indicating the extreme recency of the capture. 



The whole case is so complete in detail and so small in size that it 

 furnishes at once a perfect example of this kind of stream-adjustment 



