DIAGENESIS: ENTEROLITHIC STRUCTURE 757 



In the former, where the enclosing rocks are undisturbed, the 

 layers of brightly colored bittern salts and of gypsum often show 

 a remarkable flexuous, sinuous or disrupted character not unlike a 

 structure produced by strong compressive strains during tectonic 

 deformation. That such deformation is not tectonic can often be 

 shown by the undisturbed character of the enclosing sandstones and 

 shales. Thus, in the Salina deposit of central New York, some of 

 the alternating salt and gypsum layers occasionally show a pro- 

 nounced flexing and overfolding, while others are wholly undis- 

 turbed. This is well shown in the following illustration reproduced 

 from Everding (Fig. 159) and representing the endolithic deforma- 



IM 





LEnn 



Fig. 159. Section of the potash layers of the Berlepsch shaft near Stassfurt. 

 Scale 1:35. The vertically lined beds are carnallite; the beds 

 with horizontal dashes are rock salt; the deformed layers (white) 

 are kieserite. (After Everding.) 



tion of the potash layers in the Berlepsch salt shaft near Stassfurt. 

 Here the rock salt and the carnallite are apparently undisturbed, 

 while the kieserite bands within the carnallite layers show most 

 pronounced distortions in dififerent directions. "The forces," says 

 Arrhenius in this connection, "which have brought about this pecu- 

 liar deformation, are evidently of very local character, and con- 

 fined to the respective carnallite layers.'' Arrhenius concludes that 

 tectonic forces cannot be the cause which produced these deforma- 

 tions. (Arrhenius-4.) 



From the resemblance of the distorted layers to the convolutions 

 of an intestine, this structure has come to be known in German 

 scientific literature as "Gekrose" structure, a name first applied l)y 

 Koken in 1900. (22.) The English equivalent of this term, pro- 



