Structure of the Eastern Alps. 355 



stone and g-ypseous and saliferous marls of Ablenau (described in the first 

 chapter*), from the unconformable system of the liornf. 



Were there any doubt that the beds of the Horn are unconformable to the 

 surrounding secondary strata, it is cleared up by the section of Ressenbero-, 

 on the opposite side of the valley. The beds composing- that mountain form 

 a collective mass not less perhaps than '2000 feet thick : from top to bottom 

 they are very nearly horizontal ; and the long horizontal lines which separate 

 the several beds_, may be traced almost into contact with the inclined masses 

 of the older system. Here again we meet with the same mineralogical 

 characters we had remarked in the corresponding parts of the system of the 

 Horn. The whole mountain is composed of beds of sandstone, sand, varie- 

 gated marl, and shale, containing multitudes of fossils identical with those in 

 the sections near Pass Geschitt, and on the flanks of the Kallenbersr. We 

 may therefore safely conclude, that the beds of Ressenberg and the Horn do 

 not belong to the system of the saliferous limestone. Their age can, then, 

 be only determined, like that of every other independent formation, by their 

 collective characters, and especially by their organic remains;};. 



Section of the Overlying Deposits of Gosau in the ascending order ; Sgc. 



Having described the position of the overlying deposits of Gosau, and their 

 relations to the neighbouring mountains, we now proceed to enumerate the 

 principal natural groups into which they may be subdivided. 



1. A coarse conglomerate system, chiefly composed of fragments, more or less rounded, of 

 Alpine limestone. It is of great thickness at the Kreutz-Graben, and in other places near the 

 side of the pass leading from Gosau to Abtenau, where it rises to a great elevation up the steep 

 sides of the mountains, and rests against beds of Alpine and hippurite-limestone (fig. 11.). It 

 is seen again, as above stated, in the valley of Russbach, on the west side of the Horn, separating 

 the secondary red sandstone and gypseous marls from the overlying series (fig. 10.) ; and it there 

 appears to have derived its prevailing red colour, and some of its other characters, from the older 

 system on which it rests, and by the partial destruction of which it has been formed. 



* Supra, p. 309. 



\ Plate XXXVI. fig. 10. Figure 11. has become reversed in engraving. To see the strata 

 as here represented, the spectator must be placed in the valley of Abtenau to the west of Gosau. 

 Had Rosen-Kogel been on the right hand of the Plate, it would have then represented the ridge 

 of the Horn as seen from the valley of Gosau. 



+ In Plate XL. the great serrated chain of Alpine limestone is seen in front ; and the woody 

 flanks of the overlying ridges of the Horn and the Ressenberg are seen respectively on the right 

 and left sides of the picture. 



