138 KRAFFT: EXOTIC BLOCKS OF MALLA JOHAR. 



the pitchstone fragments. It appears that in the original limestone, 

 fragments were crushed together with the harder volcanic rocks, with 

 the result that the limestone now apparently forms the cement of the 

 breccia. Volcanic tuffs are often met with but never in a fresh condition. 

 A specimen of tuff was found by Mr. Holland to contain fragments of 

 various derivation, including quartzites and volcanic rocks. 



Age of volcanics. — The volcanic rocks of Johar are younger than 

 the flysch. This follows first from their overlying the latter and 

 secondly from the fact that blocks, derived from various divisions of 

 the flysch series, even the tuffs (4/) are met with among the volcanics. 

 The latter must be considered equivalent in age to the volcanics of the 

 Indus valley, viz.., lower tertiary. 



Origin. — As to their mode of origin they are clearly subaerial. 

 This must be concluded from their petrological and geological features, 

 and from the absence of all proof of a subaqueous origin. The 

 volcanics show no trace of bedding, the fragmental constituents are 

 angular, never rolled, and no sedimentary deposits are connected 

 with them. 



As stated in the introduction, these rocks were previously con- 

 sidered intrusive rocks, a theory which can no longer be maintained. 

 Distribution and petrological habitus clearly indicate their surface 

 origin, and this is further corroborated by their being folded together 

 with the flysch under conditions which exactly recall sedimentary beds. 

 There must of course be volcanic vents and dykes, through which the 

 igneous rocks have reached the surface, but the sources of discharge 

 no doubt lie outside Johar, viz., to the north or north-east of it within 

 Hundes, as nowhere in the area examined have intrusive dykes been 

 discovered. 1 It is true that in places volcanics are mixed up with the 

 flysch, but this can in almost every instance be proved to be the result 

 of later disturbances. 



1 I have twice followed the route along which Diener ascended from Talla 

 Sangcha towards Kiogarh No. 1, but completely failed to discover the " numerous 

 veins of intrusive rocks " which Diener reported. Nor have I observed intrusions 

 anywhere else in the flysch of Johar, although I examined this district much more 

 closely than any previous observer. 



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