128 SUB-HIMALAYAN ROCKS OF N. W. INDIA. [CHAP. IV. 



coarseness, and at last even clays and clay-conglomerates appear in 



perfectly conformable sequence. 



This section, south of Suntour Gurh, must be at least from 2 to 



3,000 feet thick ; its composition is so identical 

 Doubtful separation of 

 Nahun and lower Siva- with a portion of the Sivalik section that I 

 lik rocks. 



cannot hesitate to look upon them as one and 



the same ; and the order of succession in the Noon section shows as 

 conclusively that the series is inverted. The question then follows, 

 where are we to draw the line separating our Sivalik from our Nahun 

 groups, between these southernmost inverted clay-conglomerates and the 

 main boundary with the slate rocks. For the map a choice had to be 

 made, and I adopted the Nahun sections as a standard, drawing the line 

 at the base of the hills at Suntour Gurh. To a certain extent, I believe, 

 this to be correct. I do not think it can be doubted, that the rocks 

 north of that line represent those north of the Markunda junction at 

 Nahun, but I have serious doubts, whether the inverted strata in the 

 lower reach of the Noon can be justly separated from those to the north 

 of them. Without suggestions from other sections no one would ever 

 think of doing so ; and, moreover, any one who had come through one 

 of the passes south of Dehra and gone on to the section of the Noon 

 would infallibly look upon the rocks in both as the same. Some reason 

 for a division of the section might be made out on the strength of the 

 more vertical and crushed condition of the rocks about Suntour Gurh, I 

 have availed n^self of this pretence, but, on the other hand, this crush- 

 ing is no more than generally occurs in every section of contorted rocks 

 where the beds are thinner and more earthy. What, then, is to be the 

 compromise as regards this boundary ? I believe it will ultimately prove 

 to be that no line drawn upon the evidence of even extreme unconfor- 

 mability among this great sequence of Sub-Himalayan rocks will even 

 approximately, and in neighbouring localities, indicate corresponding 

 deposits 



