104 MIDDLEMISS: GEOLOGY OF HAZARA AND BLACK MOUNTAIN. 



These increase near the felsite above ; and it does not seem improba- 

 ble that they have some connection with the felsite (e.g., are the 

 result of contact metamorphism). Above the limestone come two or 

 three beds of the felsite, very distinctly banded and with what I 

 regard as flow-brecciation structure very visible. It is of various 

 colours, from grey to purple or dark green. The thickness of these 

 is not very great, not more than 30 feet. Above them in turn comes a 

 quantity of shales, some of which are purple and micaceous, and others 

 of a buff colour and entirely resembling those at the base of the 

 Trias near Sulhud, called Tagling by Waagen and Wynne. In the 

 upper part of the brecciated felsite there occurs haematitic material, 

 making its appearance as a sort of ground-mass in which the broken- 

 up pieces of felsite are scattered. 



This felsitic and haematitic rock may be followed in one direction 

 up to the top of the little hill marked by two trees in the view of 

 Sirban from the north (PI. 6), where it gradually assumes the 

 steep dip of the underlying Infra-Trias limestone. It is bounded 

 on the east by the north-eastern end of the north Sirban fault, 

 which takes it underneath the cliffs of genuine Trias limestone. 

 In its position on the two-tree hill it is exactly analogous to the 

 same rock on the top of Sirban hill : it has been left as a skin 

 on the north face of the two-tree hill and then caught in the 

 synclinal as described, whereas in the case of the north face of Sirban 

 it has been denuded away in all the lower parts of the mountain. 



The Infra-Trias limestone, with this single interruption of the 

 felsite and haematite, continues to occupy the northern aspect of the 

 Sirban massif as a much-contracted sub-zone up to Shakur Bandee 

 village. It is then lost under the alluvium of the Abbottabad plain, 

 to reappear again in the direction of Kakool. From the point on 

 the ridge near Shakur Bandee the great north Sirban fault is still 

 its limit in a south-easterly direction. 



It will now be convenient to cross this sub-zone boundary fault 

 and see what is the condition of things on the other side. The first 

 and most important thing noticeable is that the Trias limestone is 



( 104 ) 



