GEOLOGICAL DIVISIONS. tgg 



It is possible that a satisfactory survey might reveal some 

 penological characters, which taken in conjunction with other par- 

 ticulars might be useful for revealing the true age of particular rocks 

 where the fossil evidence is not available. But nothing of the sort 

 has been detected so far with any certainty. Thus on two occa- 

 sions, at Ka"n and at Malik Gatt where some beds were identified, 

 on account of their fossils, with the u Cardita beaumonii" stage, 

 there occur some conglomerates ; it is not always easy to distinguish 

 a rock of that nature from the volcanic agglomerates so frequent in 

 this region, but in both these instances, the pebbles although 

 volcanic have every appearance of having been rolled. They con- 

 tain a great many large fossil oysters and other shallow water 

 forms. It may be that, if the relative height of the land was greater 

 during that period, the products of volcanic activity appeared in 

 larger proportion above the sea-level, and this would explain the 

 frequency of conglomeratic beds amongst rocks of that period. 



If this be so, then, where other evidence is missing the abundance 

 of conglomerates would favour the notion that the strata with which 

 they are interbedded are upper cretaceous. But the observations 

 made so far are not sufficient to warrant this conclusion, and as to 

 many other rocks, however characteristic may be their appearance, 

 it is doubtful whether they indicate any special horizon. For 

 instance, the great masses of shales with intercalated calcareous 

 sandstone bands that occur in so many districts, such as the Toba 

 plateau, the ranges east of Nushki, the neighbourhood of Mirui, and 

 many other localities, present, especially when the degree of disturb* 

 ance is moderate, a most unmistakable aspect. In one instance 

 at Tafui, some of the sandstone bands were found to contain num- 

 mulites characteristic of the Khirthar fauna, which shows them to 

 represent locally rocks of the same age as occur elsewhere with a 

 less arenaceous facies ; but the very fact of these differences of facies 

 prevents us from concluding that they always belong to one par- 

 ticular stage, and, although so easily recognised in the field, their age 

 cannot be fixed, at present at least, where, as usual, they do not 

 contain any fossils. 



( 21 ) 



