DESCRIPTION OF SECTIONS. 2%\ 



by faulting, the exact relations of the rocks are somewhat obscured. 

 It is, however, very similar in all respects to other columnar rocks 

 which will be mentioned hereafter (pages 76, 77), and whose intrusive 

 character is well established, but whose exact age is doubtful, as there 

 exists some uncertainty as to whether they are intrusive sills 

 contemporaneous with the flysch eruptions, or whether they are 

 related to the much later granitic and dioritic intrusions which are 

 probably of upper eocene age. The granophyric micro-diorite d 

 is petrologically very similar to one of the most typical of these 

 columnar rocks. The eurite a on the other hand resembles the 

 narrower dykes and the edges of many of the large intrusions of 

 the later period. It would seem, therefore, logical to look upon all 

 the intrusive sills of the Tozgi section as belonging to the same 

 later system. At the same time, the presence of a great mass of 

 bedded volcanic products makes it necessary to consider whether the 

 intrusions might belong to the same igneous series. The breccia ^- 4 3 

 has characters relating it to a quartz-trachyte ; the lava c is a more 

 basic andesite, while the tuffs consist of fragments of many varieties 

 of acid and basic rocks. Thus the penological characters of the erup- 

 tive products are not sufficiently uniform to be taken as an argument 

 in favour of any relation between the intrusive and the eruptive 

 rocks. The question is far too complicated to be unravelled by means 

 of the observations made during the short time that I was able to 

 devote to a study of the field relations of the rocks. 



At Tozgi there are terraces of travertine of 



Travertine terraces. ° . 



the same nature as south of Jhuli (page 70). 

 „ Koh-i-Humai (called K6h-i-Rezai on the map) 



K6h-i-Humai. r 



to the north of Tozgi consists of great masses 



of hippuritic limestone. Here the strike is almost due north. The 



massive limestone, not less than 300 feet thick, rests upon shales, 



flaggy limestones, calcareous shales, arenaceous shales, arenaceous 



limestones, all these strata frequently containing volcanic material 



(spec. ^W) ( see section, Fig. 9). At d t is another of the columnar 



rocks of doubtful nature similar to the rock h at Tozgi. The 



C 73 ) 



