Chap. IV.] nahun and sivalik groups. 147 



or middle Sub-Himalayan rocks, — the continuation, in fact, of the 



line which, to the east of the Sutlej, forms the 

 The Belaspnr fault ; 1 . 



mam lower Himalayan boundary. It is not a 



continuous line in the region of the Beas, and it is interesting to see 



how the newer rocks lap across it in a manner exactly similar to that 



in which the gray sandstones of the Bubhor section laps round the 



point of the ridge north of Una. Towards the upper end of the 



Sher khud soft gray conglomeritic sandstones have a low inclination 



to eastwards on the west bank of the river 5 and on the east side 



we find deep red clays and hard purple sandstones, with a high dip 



in the same direction. Further up, about Dubrog, the contact is 



obscurely seen, and it is rather puzzling ; conglomerates of the coarsest 



description, containing well rounded boulders of quartzite and of 



granitic rocks two feet in diameter, and which are shivered to splinters 



in place by the crushing action, are found jumbled together with the 



red rocks, and not exclusively along a definite vertical band, — I found 



the conglomerate in situ 100 yards due east of a section of the 



red rocks. Crossing the watershed to the next stream on the north, the 



younger rocks rapidly assume a high westerly underlie, and then curve 



in a most regular manner round the point of the 

 its termination. 



ridge separating the Sher from the Suin, forming a 



semi-circular diverging dip, and a sloping anticlinal axis on the ridge, 



but they do not extend far either in the valley or on the ridge, older 



looking rocks cropping up from beneath them. East of the Suin 



another fissure separates them from the main area of the inner zone. 



Thus terminates the line of boundary which has so often been noticed 



already. It may perhaps be questioned whether the feature (in its faulted 



character) really dies out here, or whether it be only covered up, but 



there seems very little presumption in favour of the latter supposition, — 



the structure displayed by the younger rocks corresponds very exactly 



with the production of a fissure or slip of some extent in that position, 



