A TYPICAL CASE OF STREAM-CAPTURE IN MICHIGAN/ 



The geographic relations of the phenomena to be described herein 

 are shown in the accompanying map (Fig. i). The wider relations 

 are shown in the smaller map, the particular location being near 

 Rawsonville, east of Ypsilanti, Mich. ; while the more special relations 

 are shown in the larger map. 



The least modified and most typical remnant of the captured 

 valley to be described is shown in Fig. 2 — a view taken from the 

 point A on the larger map, and embracing the upper part of what is 

 now the Oak Run valley. The valley seen in the foreground has a 

 typical trough-like configuration, with very definite slopes which make 

 a distinct angle of 20° with the flat and marshy valley floor. No 

 stream, however, flows through this portion. In the middle distance 

 the valley floor terminates abruptly on the side of a deeper valley. 

 The termination is given artificial distinctness by a roadway crossing 

 at this point which has been raised about three feet on account of 

 the marshiness of the valley floor. Nearly opposite this abrupt 

 end of Oak Run valley, another valley. Oak Ravine, comes in obhquely 

 from the right, as partially shown by the snow-covered slope near the 

 group of elms in the middle of the picture. This valley heads in a 

 clump of oaks, the tops of which are visible in the right background. 

 The drainage of the valley is discharged opposite the truncated head 

 of Oak Run valley. At the point of their nearest approach, in the 

 left center of the view (Fig. 2), Oak Run and Oak Ravine are inter- 

 cepted by an embayment of the Huron River flood-plain, whose 

 bluffs are here about forty-five feet high. This embayment was 

 made by a meander of the Huron River which cut back into the drift- 

 plain of the region about a quarter of a mile, and reached the line of the 

 two valleys in question (see map. Fig. i). This drift plain consti- 

 tutes the horizon in Fig. 2, and the bluff of the embayment is partially 

 shown at the left below the barn. 



I I am great!}' indebted to Professor M. S. W. Jefferson for the accompanying 

 photographs and for helpful suggestions in the preparation of this paper. 



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