GLIDING DEFORMATIONS 



781 



Examples of fossil subaqueous solifluction. 



A. Miocenic sublacustrine glidings of Oeningen. The Miocenic 

 marls of Oeningen, noted for their wonderful remains of insects, 

 etc., show in the midst of these beds a strongly folded layer, lying 

 between horizontal beds of the same character. These foldings are 

 so pronounced that they inevitably suggest lateral compression as 

 the cause of their production, yet the entirely undisturbed charac- 



FiG. 164. Folding accompanying snbaqnatic gliding in Miocenic marl of 

 Oeningen. One-half natural size. (After Hcim.) 



ter of the enclosing strata forbids such an assumption. Another 

 feature which indicates gliding is the independence of the folded 

 beds from the basal beds, against which the limbs commonly abut 

 directly. The axes of the folds are notably thickened, while the 

 limbs are thinned by compression exactly as in tectonic folding. 

 (Figs. 163, 164.) 



B. Jurassic deformations of this type are known from the 

 Solnhofen Plattenkalke, where the so-called distorted layer (krunune 

 Lage) furnishes a good example. The zone has a thickness 

 of I to 1.5 meters, and in it are found all the phenomena of 

 folding, including folds 5 meters in length. Here the glidings took 

 place in the periodically submerged lagoons within the reefs and the 



