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Indiana University Studies 



limestones. In strata where folding has occurred, stylolite- 

 seams are sometimes found along the inclined bedding planes 

 with the individual columns themselves vertical instead of at 

 right angles to the bedding planes. Evidently the stylolites 

 developed after the lateral compressive forces ceased, their 

 development being in response merely to the vertical static 

 pressure due to the weight of the superincumbent rock — the 

 inclined bedding plane providing an avenue for ground water 

 circulation. Examples of such are noticeable in the steeply 



Fig. 22. — Diagram of stylolite-seam along an inclined bedding 

 plane, where the position of the individual columns is 

 vertical, instead of at right angles to the plane of strati- 

 fication. Observed in the steeply inclined strata of the 

 ''Niagara domes" of northern Indiana by Professor E. R. 

 Cumings. 



inclined strata of the so-called "Niagara domes" of Northern 

 Indiana (see Fig. 22). Where lateral pressure exists, hori- 

 zontal and angular columns may develop along vertical and 

 angular crevices, the direction of penetration of the columns 

 depending upon the direction of the pressure. The occur- 

 rence of such is described by Fuchs. Reis, Wagner, Gordon, 

 and others. 



The above discussion shows that a great number of stylo- 

 litic variations and complexities are to be expected, and can 

 be explained by the solution theory. A discussion of the 



