1848.] MURCHISON ON THE STRUCTURE OF THE ALPS. 



251 



This ingenious explanation of Professor H. Rogers may, it appears 

 to me, be very well applied to those examples in the Alps where, as 

 assumed by him in his diagrams, the strata of different ages have 

 originally been continuously and conformably superposed. Such, 



Fig. 29. 



Fracture through the anticlinal axis-plane of an inverted flexure {the elevated 

 mountains are to the right hand). 



No. 1. Commencement of 

 fracture after flexure. 



No. 2. After fracture and 

 displacement. 



No. 3. After denudation. 



Fig. 30. 

 Fracture through the synclinal axis-plane of an inverted flexure. 



No. 1. Fracture before 

 displacement. 



No. 2. After disDlacement. 



No. 3. After denudation. 



for example, may have been the case in all those tracts where the 

 cretaceous rocks were formerly surmounted by nummulite limestone 

 and flysch, and where, after having been thrown into inverted anti- 

 clinals and synclinals, they were afterwards fractured and denuded in 

 the manner described. Of this class of faults the figures 16 and 19 

 may be cited as very probably answering to the law of displacement 

 observed in the United States*. In the first of these, near Dornbirn, 



* I say probably, because in the Alps the subterranean course of faults has not 

 been ascertained by mining operations as in the United States, and examination is 

 usually much impeded by vast quantities of detritus. 



