176 KRAFFT: EXOTIC BLOCKS OF MALLA JOHAR. 



forces us to suspect the sources of discharge to lie much farther to the 

 north. 



It would appear either that the facies changes very rapidly or that 

 the erupted masses are spread over an enormous area. As both these 

 eventualities seem equally improbable, we find ourselves face to face 

 with an obstacle, at present unsurmountable. 



Events hef ore and after the volcanic eruptions.- — Having in the 

 foregoing discussed the volcanic outbursts, which gave rise to the exotic 

 blocks, we must now consider the events that happened before and 

 after the eruptions. 



In the first place the age of the uppermost flysch beds will have to 

 be discussed, a question which has so far scarcely been touched upon. 

 To arrive at a conclusion we must start from the Indus valley tertia- 

 ries. The nummulitic beds of this area are limestones, shales, sand- 

 stones and conglomerates, with which the volcanic traps are in the 

 main contemporaneous. 1 The nummulitics appear to extend eastwards 

 as far as the area north of the Niti pass, for Mr. Griesbach mentions 

 contorted nummulites from a series of altered beds, which also is 

 connected with igneous rocks. 2 



Flysch in its entirety of cretaceous age. — The features observed 

 in Johar are however entirely different. We have seen that subaqueous 

 tuffs appear in the topmost flysch series, but these are of small thick- 

 ness and cannot be compared with the contemporaneous traps as re- 

 corded from the Indus valley. Limestones with Nummulites were 

 nowhere found. On the other hand we meet with subaerial volcanics 

 which overlie the tuffs and are decidedly younger, including as they do 

 fragments of the latter. At the same time these volcanics are free 

 from any contemporaneous sedimentary beds. Now we cannot but 

 assume that the lavas of Johar have been erupted during the same 

 period as the traps of the Indus valley, viz., that they are of eocene 

 age. The most likely conclusion therefore is that the flysch does not 

 reach into the lower tertiaries, but is in its entirety of cretaceous age. 



1 Lydekker. Memoirs, XXII, p. III. 



2 Memoirs, XXIII, p. 83. 



( 5° ) 



