Chap. IV.] nahun and sivalik groups. 14$ 



There can be no doubt however that the downthrow is on the north-east, 

 i. e., with, not against, the direction of the axis-plane of the flexures. 

 It were premature at present to insist upon the amount of throw 

 of these faults ; if we are to conclude that all these deposits once 

 covered the whole area to an equal depth, the throw must be enor- 

 mous, but it seems possible that these flexures may have been more 

 or less formed prior to the completion of the series, and hence the irre- 

 gularities of present position may have been to some extent ah origine. 

 The fact, however, already mentioned in the Hurdwar section, is equally 

 applicable here, — the newest rocks, that are disturbed at all, seem to have 

 undergone as much disturbance as the others. In the mode of termina- 

 tion of the Naina Devi ridge we have examples, though somewhat irre- 

 gular, of the passage of the same contortion from being folded to being 

 normal and symmetrical flexures. 



Before passing on to the north-east I will rapidly notice the extension 



Extension to the Eavee of tnis second zone up to the Ravee. The con- 

 of the Naina Devi flexure. ,. ,,. r .-, rr n -., . 



tmuation 01 the Koseree fault seems to coincide 



with a sharp synclinal fold passing obliquely along the north-east point 

 of the Pur wain or Gungot ridge ; and further to the north-west it 

 may correspond with the synclinal or the uniclinal curve of the strata in 

 the dun beyond the Beas. The Purwain ridge is the representative, 

 and, in a manner, the continuation of the Naina Devi ridge, but the 

 features are altogether changed; it is a broad flat ridge of the ordinary 

 Sivalik type. A low north-easterly dip prevails throughout, and thick 

 boulder conglomerates reach up to the crest, sandstones and clays crop- 

 ping out along the south-western slopes to the Una dun. There is pro- 

 bably a sharp double curve concealed beneath the dun, for conglomerates, 

 though less coarse than those on Purwain, come in again on the inner 

 slopes of the outermost range. In the gorge of the Beas, through the 

 Purwain ridge, there are excellent sections, showing rather complicated 

 disturbance, which we may reasonably infer to be local ; the rocks are the 



