Structure of the Austrian Alps, fyc. 99 



Salzburg country, the geological evidence on that side of the 

 chain is not so complete as in the neighbourhood of Bleiberg. 

 Ammonites and Belemnites have been found, though rarely, in 

 the lower part of the great precipices which surmount the red 

 sandstone series near Werfen ; but we are not aware that the 

 Gryphaea incurva has ever been seen along with these fossils. 

 The argument from analogy is, however, sufficiently convin- 

 cing where we have nothing to oppose to it. We therefore 

 venture to conclude, that the great system of the older Alpine 

 limestone, overlying the red sandstone, commences on both 

 sides of the chain with the lias. Its precise superior limit we 

 are not able to indicate ; but we believe, from its enormous 

 thickness, as well as from some of its fossils, that it ascends 

 considerably into the oolitic series*. 



5. Limestone with subordinate salifcraus Marls, fyc. fyc. 

 No mines of salt have, we believe, been worked in the for- 

 mation of red sandstone and gypseous marls which underlies 

 the older Alpine limestone. All the principal deposits of that 

 mineral are in a much higher position; being incased in the 

 calcareous system of the Alps, and distinctly overlying the 

 older Alpine limestone. This fact appears to be incontesta- 

 bly proved in the memoirs of M. de Lill de Lilienbachf ; 

 to whose kind assistance and instructions we were greatly in- 

 debted during our visit to the Salzburg Alps. 



* Along the line of our transverse section, we in vain looked for that 

 structui'e which is so characteristic of many of the secondary rocks of Eng- 

 land ; and in no instance did we discover a single specimen of true oolite. 

 In the range of the calcareous zone along the southern flanks of the Bather 

 Gehirge, and from thence towards the lower regions bordering on the Da- 

 nube, the rocks, however, occasionally exhibit the external characters of a 

 part of our oolitic series. Thus, near Gonowitz, we found beds of a yellow 

 colour, and a coarse open texture, somewhat resembling cornbrash, and 

 containing many well preserved fossils. At the time, we were not aware of 

 the rarity, and consequent interest, of these phenomena; which are well de- 

 serving of a much more careful examination than we bestowed upon them. 



On the great road from Cilly to Laybacli, there are some highly interest- 

 ing sections, especially near Franz and St. Oswald, where great beds of 

 shale alternate with coarse, reddish sandstone resembling millstone grit ; 

 the whole being surmounted by masses of rauchwacke and other modifica- 

 tions of dolomite. In the same neighbourhood are several beds of coal, 

 which we wished to visit, as we supposed them analogous to the coal de- 

 posits we had seen, subordinate to the newer secondary system, south-west 

 of Vienna. We were however disappointed in our hopes of seeing them ; and 

 we have been since informed that they all belong to formations of tertiary 

 brown coal. We mention these facts, not in the expectation of throwing 

 any light upon the structure of this portion of the Alps, but in the hope of 

 directing the attention of future observers to the interesting phenomena of 

 the calcareous chain between Gonowitz and Laybach. 



t Zeitschr fur Mineralog. No. x. 1828; and Bulletin des Sciences, Mai 

 1829, &c. &c. 



O 2 In 



