DESCRIPTIVE GEOLOGY : GENERAL CONSIDERATIONS. 277 



The next question before us is what was the upward limitation in 



the stratigraphical series of this metamorphic 



JStiy^Jt influence? What are the highest or youngest 



enced by this metamor- stra t a so affected ? In Hazara that question has 



phism. ^ 



been partially answered. The Trias limestone 

 we know to have been unaffected in this, way ; the Infra-Trias 

 (whose age is uncertain) has been metamorphosed in a minor degree, 

 but much if not all of this metamorphism may be attributed to the 

 eruption of the basic dykes among them, an event which was of later 

 date than the appearance of the gneissose-granite. The Slate series 

 has, of course, been so metamorphosed. Hence the limit in Hazara is 

 Pre-Triassic and possibly Pre-Infra-Triassic. 1 



In many parts of the Lower Himalaya the stratigraphical sequence 

 of rocks from the secondary epoch downwards are unrepresented, and 

 so no useful data can be supplied from the Indian side of the main 

 range. But in the direction of Tibet on the north side of the great 

 crystalline massif, as in Spiti, Garhwal and Kumaun, etc., the tran- 

 sitional metamorphic rocks (Haimantas and Vaikritas of Griesbach) 

 are older than Devonian and possibly than Silurian. The great block 

 of the historical strata that form the northern range of the Central 

 Himalayan or Tibetan watershed, consists of shales, limestones, and 

 sandstones, not only with a complete absence of granitic rocks intrud- 

 ed among them, but with all semblance of mineral change wanting in 

 them too. 



In Kashmir part of the Panjal system is described by Lydekker 

 as having been metamorphosed, but, as has been shewn before when 

 discussing the Infra-Trias conglomerate, it is possible that Mr. 

 Lydekker's Panjal system is unnatural, inasmuch as it embraces two 

 great formations separated by a conglomerate, which, in Hazara at 



1 Since the above was written, General McMahon in his most interesting Presidential 

 address to the Geologists' Association, 1895, still upholds the Tertiary age of this 

 granite. After what has been said above concerning its identity (undoubted I think) 

 with the granita referred to by him, and concerning the Laichi Khun section, its Ter- 

 tiary age is plainly impossible. Besides this, the most straightforward proof of such 

 a conclusion is entirely wanting, namely the occurence of the granite intrusive among 

 those Tertiaries at any single point from end to end of the Himalaya. 



( 277 ) 



