GEOLOGY. 27 



On comparing both sides o£ this list, it will be seen that the con- 

 tinuation of the Salt Range presents no exception 

 The series. . 



to the changeable character or the sections which 



affects the whole chain from its eastern to its western regions. The 

 newer formations are most alike throughout, the older palaeozoic series 

 most dissimilar, to those of this region. The mesozoic rocks are like- 

 wise differently developed; but the stratigraphically united zone com- 

 prising the carboniferous and triassic formations is common to the 

 country on both sides of the Indus. Eastward of the Indus the speckled 

 sandstone group just beneath the carboniferous has reached its greatest 

 development, becoming fugitively present towards this river, but beyond 

 it to the westward the group is unknown to occur anywhere. 



In localities where it does occur east of the Indus, there intervenes 



between it and the salt-marl the set of dark 

 Changes in the series. . 



purple boulder beds already stated to exist m the 



Khasor range, and (in the absence of the speckled sandstone) to underlie 



directly the carboniferous group. But the sections are unlike : cis-Indus 



the boulder beds rest immediately on the salt-marl and gypsum : in this 



country they contain gypsum bands in one place, and in another they 



overlie a group of chemically formed magnesian and gypseous rocks, 



entirely unlike the Salt Range saline series, and moreover resting on 



purple sandstones similar to those which are well known to overlie 



that series. 



Hence it would appear that the boulder beds are really much newer 



than the purple sandstone, and are separated from 

 Kelations. Boulder heds. 



it by a gypseous and dolomitic group unknown 



in the Salt Range. 



This additional information afforded by the trans-Indus sections 



would thus give the following arrangement for the oldest portion of the 



whole Salt Range and trans-Indus Series : — 



4. Purple houlder beds containing trap, red granitic and other crystalline well-rounded 

 blocks, some of which are polished and show slight striation (glacial ?). Ked 

 and white gypsum layers occur in the group trans-Indus. 



( 237 ) 



