GEOLOGY OF IKE UPPEJ* fUNJAJi. 367 



Upper part of group D = Upper Siwalik, Conglomerates. 

 Groups B, C, and lower 



part of D = Lower Siwalik, Sandstone and clay. 



Groups A and E . . . . = Murree Beds, Sandstone and clay. 



These rock groups exhibit throughout marked conformity of 

 superposition and, from their intercalation with the underlying 

 Eocene rocks, of course complete conformity with them also, so far 

 as parallelism of stratification is concerned. Oblique lamination and 

 current-marks occur, but the beds present no structural peculiarity 

 to indicate that they were always accumulated at steep angles of 

 deposition, or formed banks with sufficiently distinct irregularity of 

 shape and thickness to become evident or prominent in the strati- 

 graphic aspect of the series. Nor is there any thing to mark the 

 place at which the marine conditions of the Eocene period become 

 changed into freshwater ones at later times. Although very large 

 land and partly aquatic animals, with many smaller ones, have left 

 their remains more or less generally distributed, it is only near the 

 upper limits of the Lower Siwalik groups that I have found fossil 

 freshwater shells (Unionidse). 



It has been observed of other regions south of the middle part of 

 the Himalaya Mountains*, that it is not to be supposed the whole 

 thickness of the Tertiary sandstones &c. was ever strictly super- 

 posed vertically, but rather that' these deposits (or the newer ones 

 at least) were laid down bankwise, each overlapping an older bank 

 and extending beyond its lateral limits in one direction, the deposi- 

 tion taking place contemporaneously with a gradual elevation on the 

 side from which the materials come. 



In attempting to apply this mode of deposition to the ground 

 under notice it will be seen that the newer rocks are distributed in 

 a zone having some parallelism to the contour of the hills, but 

 situated nearer to the Salt Range than to the Himalayan area. This 

 arrangement of the newer zone is due partly to the smaller thick- 

 ness of the Murree beds southwards, and partly to the more intense 

 folding and disturbance of that older group in the other direction, 

 which would cause them to occupy more ground. 



Whether this greater intensity of disturbance was actually taking 

 place, accompanied by elevation, during the deposition of the Siwalik 

 beds, there is little to show. Still a few scattered pebbles of hard 

 Murree sandstone and of JSTummulitic limestones, occurring in con- 

 glomeratic beds among the Siwalik strata, on different horizons, 

 afford some indication that both to the north and south of the Pindi 

 plateau (probably at a considerable distance) these older rocks 

 had been elevated sufficiently to undergo denudation beyond the 

 limits of the depositing area of which the plateau then formed 

 a part. 



It may be that the whole of the detrital Tertiary rocks were 



* Memoir on Kumaun and Garkwal, in the North-Western Provinces 

 Gazetteer (India). 



