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Some Peculiaeities in the Valley Ekosion of Big Creek 

 AND Tributaries. 



Glenn Culbertson. 



Big creek and tributaries in Jefferson county, Indiana, present some 

 interesting features in their erosive worl<. The most striliiug of these, 

 presented by a map of the stream and its affluents are, on the one hand, 

 their almost uniform flow in a westerly direction, or, on the other hand, 

 in a course almost at right angles with those flowing westward. 



These characters are clearly shown in the northerly courses of Lewis 

 and Little creeks, while their tributaries flow in a westerly direction. The 

 same is true of Big creek and its other tributaries, as may be seen in the 

 central and northern parts of the map. Clifty creek, a smaller stream 

 emptying into the Ohio just below Madison, has the same peculiarities, as 

 has also the upper portion of the West Fork of Indian Ken.'ucky creek. In 

 these eases the main stream flows south, while the tributaries enter from 

 the east and northeast. 



Another interesting feature so noticeable in certain parts of Big 

 creek and its larger tributaries, where the flow is either northerly or 

 southerly, is their remarkably meandering courses. We have been taught 

 that meanders have been found almost exclusively in streams of gentle 

 slope and with banks of alluvial soil. Both of these characteristics are 

 entirely wanting in the valleys here referred to. In the case of several 

 of the meanders the stream after flowing from one to two miles around 

 a curve, returns to within a vex'y short distance of the starting point. 

 The banks of the stream, as well as the sides of the valley, where the 

 meanders are prominent, are almost perpendicular cliffs on the convex 

 side. These cliffs reach the height of lOo to 150 feet in the lower portions 

 of the stream. The concave side of the meanders have gentle slopes from 

 one-fourth to one-half a mile in length. 



The peculiarities in the v.alley erosion of these streams is largely due 

 to the structure of the rocks. The rock strata of this region dip gently 

 towards the west and southwest. The amount of this dip in the more 



