Chap. IV.] nakun and sivalik groups. 137 



proceeded : in the section of the Sutlej the necessarily great difference 

 in age between the conglomerates of Belaspur and of Bubhor is at once 

 apparent, and would fairly be extended to the representative beds to the 

 north-west, irrespective of the failure of the original distinguishing 

 characters ; whereas, in coming from the north-west one would consider 

 all the rocks of the Kangra duns as Sivalik, till brought to a check 

 by the section of the Sutlej. I do not see any way out of the dilemma, 

 but I am aware that my study of this large area has been after all 

 superficial, and inadequate to niceties of classification. 



There are some very interesting questions connected with the portion 

 of middle Sub-Himalayan rocks we have just examined between Kalka 

 and the Sutlej. Is the fact of the greater proportion of the lower 

 beds in this area, and the gradual disappearance of the upper beds to 

 the south-east, due entirely to the greater contortion and consequent 

 elevation and denudation of the upper beds, or does it involve elevation 

 independent of contortion, and if so, was this prior to or subsequent 

 to the deposition of the Belaspur beds? The result is one of the same 

 kind as I have, in the case of the Subathu group, taken to prove a 

 general easterly upheaval of the area. A close examination of the mode 

 of thinning out of the top beds in the valleys of the Gumber and 

 Gumrola would help to solve the problem ; but the full solution of it must 

 await the discovery of fossils by which the relative ages of these doubtful 

 middle bands may be fixed. It has occurred to me as possible that the 

 bottom beds of the Sutlej area may be the records of at least a part of 

 the long period of denudation which I suppose to have intervened 

 between the Subathu and the Nahun groups of the eastern region, — they 

 may be the very debris of that denudation. Or once more I will ask 

 the question, may these bottom rocks of the Sutlej area not belong to the 

 Subathu group, — may not the difference of composition, which is after all 

 not very great, be accounted for by local conditions of the time ? May 

 not the ridge of limestone, now separating the two areas, which I 



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