DELHI QUARTZITE SERIES. 95 



If it were only their lie with regard to the superincumbent and 



Their position as widely developed Phyllite Series that 



regards the Phyllite needed consideration, the matter would 



Scries. 



not be beyond fairly easy expression. For 



instance, the positions (1) near Od, (2) west of Navugam, (3) 

 Dev Mori, and (4) Kundol, are all instances of a rapid passage 

 from the qUartzite series up into the phyllites. The regular in- 

 terdigitations of the quartzite outcrops with the phyllites and 

 the resulting deep sinuosities of outcrop, are just what would be 

 expected in a much folded combination of two such widely 

 differing lithological types that at the same time are conformable. 

 In anticipation of the descriptions of the Phyllite Series that will 

 be found further on. I must assume here its complete distinctiveness 

 from all the Aravalli schists and gneisses : the uniformity of the 

 one series and the great diversity of the other from point to point 

 is by itself sufficiently conclusive. But, even apart from this, 

 their position and interbeddings with the Delhi Quartzite, as seen 

 for example west of Chitoda. all round the ridge of quartzite between 

 Od and Navugam. on the eastern side of the ridges from between 

 Dev Mori and Kundol down to the neighbourhood west and south- 

 west of Sangal in the Ma jam valley, make their position sufficiently 

 clear as coming in sequence above the Delhi Quartzite. Through- 

 out all these areas, the upstanding outcrops of the phyllites, 

 strengthened by their resistant quartz veins, give one plenty of 

 solid hill-sections illustrating this position. 



On the other hand, the position of the Delhi Quartzite to the 

 „,, . _ Aravallis which latter have been described 



I heir position as ,, _ , . 



regards the Aravallis. as occupying the great flat plain, almost 



wholly covered by alluvium, that stretches 

 N.— S. from Jesangpur to below Bamanvada, and VY.— E. from 

 Kheradi to Khercha and Samalpur, is far from being as clear as 

 could be desired, and must be carefully discussed. The mere out- 

 line of the quartzite series towards the plain containing the Ara- 

 vallis tells one but little. It is hopelessly irregular, without any 

 simple interdigitations corresponding to those shown by the quartzite 

 towards the phyllites. Whilst some of this irregularity such as 

 exists between Abhapur and Khercha (Kherancha) may be the 

 result of a surface filling of alluvium in the plain, this cannot, I 

 think, explain all or even most of this irregularity. 



H 2 



