1854.] SCHLAGINTWEIT BAVARIAN ALPS. 353 



Alpe, into very irregular and puzzling stratigraphical relations to the 

 older formations. 



Tertiary Formations. 



Proceeding farther to the north in the Valley of the Amper, we find 

 of later formations the Eocene Flysch with Fucoidea in great de- 

 velopment, and the tertiary strata of Kohigrub Rottenbuch and the 

 Peissenberg ; but these do not belong to the subject of this paper. 



The diluvial deposits, which cover to a great thickness the large 

 valleys in the interior of these movintains as well as the elevated 

 plains of Bavaria, will be spoken of in the last part of this paper. 



§ The Elevatory Relations of the Rock-masses {Hehungs- 

 verhaltnisse.) 



In the mountain group under consideration, there is a very im- 

 portant and extensive system of joints, which are quite independent 

 of the stratification. 



These joints are especially well developed in the hard upper Al- 

 penkalk ; but they extend into the liassic marls, as well as into the 

 dolomites. It is evident, 1st, that these joints, which can often be 

 followed to great distances, retain very often in the same district a 

 very regular mean direction ; and 2ndly, that in the same district dif- 

 ferent systems of joints occur, crossing each other at various angles. 



I will mention some more special examples of these phsenomena 

 in the Hollenthal, where they are particularly well developed. I had 

 here also the opportunity, by the mining operations conducted at 

 different spots, to follow these joints in the interior of the mountain 

 masses. The mean strike of the one predominant system of joints 

 runs from N.E. to S.W. (N. 25°-50° E. to S. 25°-50° W.). 

 They stand almost vertical, and their sides are, generally speaking, 

 smooth and somewhat polished. They can be traced to great distances 

 along the steep escarpments of the mountains, and along the course 

 of different small rivulets, which especially follow the direction of 

 these joints, where they have produced remarkably deep erosions. 



Besides this system of joints, I could observe in the Hollenthal 

 another subordinate system, running from W.N.W toE.S.E. They 

 are by far less extensive and regular. In some places where both 

 systems are well developed and exposed, as in the Hollenthalkahr 

 and the surrounding bare ridges, they are seen mutually intersecting 

 at very high, sometimes nearly right angles. By these intersections 

 many derangements of the rocks are produced. 



Attentively following these long joints, we are soon aware of a cer- 

 tain connexion which evidently exists between their mean direction 

 and the direction of many valleys and steep mountain escarpments ; 

 and we are naturally led to the conclusion that the formation of 

 many valleys, or many ridges and steep escarpments, which can in 

 no way be explained by the strike or the inclination of the strata, are 

 due to the same causes which have produced these long joints and 

 faults. 



