152 SUB-HIMALAYAN ROCKS. OF N. W. INDIA. [CHAP. V. 



Chapter V. — Post-Sivdlik Deposits. 



I HAVE already had to notice undisturbed deposits covering vertical 

 strata to an inconsiderable thickness, yet (doubtfully) connected with the 



upper Sivalik period. The great formation of 

 Well-marked separa- 

 tion of Sivalik and Gan- later date with which one might seek to co-ordi- 

 getic rocks. 



nate such deposits chronologically is the Gangetic 



formation. Between the Sivalik strata and those of the Gangetic plains 

 there is the most decided separation ; there is no approach to a shading 

 off of disturbance, merging the one into the other. We have seen this to 

 be very marked in the eastern regions, in the sections of the Ganges and 

 the Jumna, where the most southern Sivalik rocks have a nearly vertical 

 dip. In the western district the general contrast between the forma- 

 tions is not quite so striking at the contact, but the argument is con- 

 firmed by the fact that the state of disturbance of the outermost range 

 is as great as that of the range inside it : for instance, in the section 

 between Deihreh and Hoshiyarpur, the Purwain ridge is composed of 

 probably the same strata as those of the outer ridge ; be this, however, 

 as it may, the highest underlie found in the whole section is along the 

 edge of the plains, where it is 70° to southwards. Although little evi- 

 dence exists in the narrow band of Sivalik rocks now exposed along the 

 outer fringe of the mountain-region of a diminishing intensity of disturb- 

 ance in a south-westerly direction, we may, I suppose, presume that such 

 actually occurs in the extension of these strata beneath the Gangetic 

 formation. 



The great accumulation of boulder gravel which everywhere covers 



. „ . the south base of the Sivaliks, can scarcely be 

 Limits of Gangetic J 



deposits. looked upon as belonging to the group of depo- 



sits I here speak of as the Gangetic formation. These conglomerate 



