118 ?WYNNE : GEOLOGY OF THE SALT RANGE IN THE PUNJAB. 



tion or overlap. Had some o£ these groups extended further, difficulties 

 in the way of placing several of the others would have been removed. 



The intervals left unrepresented, by the limited extension of certain 

 of the groups, must be very considerable, and each case of the kind 

 points to a break in the whole series similar to that contended for by 

 Mr. Medlicott with respect to the nummulitic and newer tertiary 

 boundary. It cannot be supposed, for instance, that while some causes 

 limited the carboniferous rocks to one end of the range, carboniferous 

 deposition was not going on somewhere else. If this limitation of 

 deposition were observable only with regard to one formation, it would 

 seem less strange, but there are here at least six or seven instances of 

 circumscribed deposits of different geological ages, from possibly pre- 

 silurian upwards. What the conditions were which thus confined the 

 deposits of a geological system so extensive in time, with so few indi- 

 cations of even local unconformity, and restricted to the comparatively 

 small area occupied by the Salt Range, is a difficulty which may be 

 pointed out, but which I cannot at present explain, 



Trans-Indus appearances of unconformity are stronger, but, so far 

 as yet seen, are chiefly limited to the basal and upper boundaries of 

 the cretaceous beds; the junction between the carboniferous limestone 

 and tertiary sandstones, &c., of Kaffir Kot (south), is perhaps also 

 an instance in which the older rock has been denuded before the deposi- 

 tion of the newer formation. 



The general absence of discordance in the series on this side of the 

 Indus must be taken as evidence of enormously prolonged tranquillity, 

 extending through all the epochs of palaeozoic, mesozoic, and csenozoic 

 time ; and yet these tranquil conditions can have been but very local, for 

 besides the unconformity just mentioned beyond the Indus, there is the 

 most palpable discordance at Sirban Mountain in the Himalayan region 

 between the infra- triassic beds and the underlying slates supposed to be 

 Silurian — a formation of which the Salt Range representative is perfectly 

 conformable with the rest of the series. 

 ( 118 ) 



