THE PATLI DON. 67 



bed. The latter now widens out, horizontal chaors and alluvial flats 

 become more common, and the river winds to a greater extent than 

 before. So abundant are the natural sections in the river cliffs that 

 all the petrological characteristics of the two rock stages, in this 

 section along the Pelani, are passed in review like an open book of 

 which not a page has been effaced. 



As will be seen by the map and the horizontal section VI, the 

 centre of the synclinal in the sand-rock stage is broken by a slight 

 vertical fault, of no constructive importance, it being a mere fracture 

 of the same kind as that dividing the sand-rock from the Siwalik 

 conglomerate further south. North of it higher dips in the opposite 

 direction set in amongst beds of slightly higher horizon than those 

 to the south of it. They soon become vertical and then inverted 

 against the next reversed fault at Halduwala. The appearance of 

 these sands, clays and loams, softly tinted of an ochre, brown, and 

 purple colour, and in an absolutely vertical position, is a strange sight 

 to one accustomed to the gentle undulations of the Tertiary strata in 

 England. Slates and schists we are accustomed to see in highly in- 

 clined positions, but to witness these sediments of yesterday (geo- 

 logically speaking) in so incongruous a position fills one with wonder. 

 We follow their vertical lines into the air above the level cliff-top, 

 but we can never conceive in their entirety the great piles of mate- 

 rial that have vanished by denudation since the Middle Siwalik 

 age. 



The fault at Halduwala (35) is of the same nature, structurally, as 

 the previous reversed fault, though it does not appear to be of so great 

 magnitude. Beds moderately low down in the sand-rock stage on 

 the south of it are in contact with lowermost Nahans on the north, and 

 the change from one to the other is sufficiently striking to the eye 

 and hammer; though of course not so vivid as that between the Siwalik 

 conglomerate and the Nahans in the Rdmganga. The fault, therefore, 

 indicates a similar compression of the strata resulting first in a mono- 

 clinal fold, then a sigma-flexure, and then a tearing along the middle 

 limb of the sigma-flexure and production of a reversed fault. To- 



E 2 ( 125 ) 



