68 MIDDLEM1SS: GEOLOGY OF HAZARA AND BLACK MOUNTAIN. 



With reference to the preceding figure it may also be remarked that 

 though there is a slight banding of the material of the vein there is 

 no foliation at all. 



In the next figure (fig. 2) I give another example of a similar kind 

 of intrusion. Here also there is a rough banding of the material 

 of the vein, inasmuch as the schorl in minute specks lies parallel to 

 the walls of the vein. The vein has, however, no true schistosity with 

 tendency to split along it. 



Of the three bands seen in 

 figure 2, the middle one cuts 

 quite diagonally across the folia- 

 tion and original bedding of the 

 schistose arenaceous rock. In 

 the diagram, A B is the direction 

 of original bedding of the schist, 

 and A A the direction of split- 

 ting in the rock, along which 

 there are fine films of mica de- 

 veloped. 



Other effects of a similar 

 kind will be detailed in the de- 

 scriptive part of this book. 



One habit of the gneissose- 

 granite has already been alluded 

 to in the paragraph describing 

 the more highly metamorphosed 



* ig ' 2 rocks. I refer to its appearance 



Note. — Gn. Gr. = Gneissose-granite veins. , . . 



A B-Schist and q uart z ite. of having been forced into the 



schist, as it were, under enormous pressure, so that it has not merely 



invaded them in a lethargic way in broad distinct bands, or with but 



an outer fringe of apophyses wandering and ramifying through the 



rocks, as I have just described, but has also permeated the rock along 



the foliation planes in a great system of minute veins all parallel 



(though sometimes with wavy parallelism) to one another. In some 



( 68 ) 



Fig. 2. 



