1V4 michiga:n academy of science. 



WIDTH OF MEANDER BELTS. 



BY MARK S. W. JEFFERSON. PROFESSOR OF GEOGRAPHY STATE NORMAL COLLEGE, 



Y'PSILANTI, 



(Full Paper in National Geographic Magazine. Extract of Conclusions Read). 



The meandering of rivers is known to vary with their size. Of those 

 streams of gentle gradient which affect a winding course, the larger 

 wander farther from side to side. 



An attempt to determine the relation between volume and width of 

 meander belt failed from insufficiency of available data, but suggested 

 that width was far the most important element of volume to affect 

 meandering. 



From a study of the best mapped rivers in Europe and this country it 

 appears that the extreme width of country over which the meanders range 

 from side to side before being abandoned by "cut-offs" in the course of 

 the river is about 18 times the width of the stream when bank full. Thus 

 a stream with well marked banks averaging 100 feet apart may meander 

 from side to side over a belt of country 1,800 feet wide. At this width 

 cut-offs are almost certain to occur. They often occur at far less width. 



The argument is empirical from tabulated measurements. Theoretical 

 considerations are cited to account for tendencies, i. e., qualitatively, but 

 no reason is found for the ratio 18 to 1. 



