52 



GRIESBACH : GEOLOGY OF THE CENTRAL HIMALAYAS 



ingly a very gradual passage from the micaceous schist south of that 

 village, into greenish-grey phyllites and talcose schists with garnets 

 of the vaikritas, and finally into the thin-bedded quartzites, shales and 

 conglomerates of the haimantas, and the change is so gradual that a 

 boundary line could not be drawn with anything like accuracy 

 Similar characters prevail in the Bissahir sections, and partially also 

 in the Spiti area; but, on the other hand, at Niti, Goting and Malari 

 the purple quartzites and conglomerates rest directly on thick-bedded 

 granitoid gneiss, and the boundary is much affected by granite in- 

 trusions. It is in fact part of the dislocation, along which the gra- 

 nites have appeared, — a gigantic overthrust. 



The purple quartzites and conglomerates are in all sections over- 

 laid by a great thickness of greenish-grey phyl- 

 2. Division. . 



lites, shales and thicker-bedded quartzites, tra- 

 versed by many quartz veins. Towards the upper portion of it. 

 reddish-brown or pink quartz shales are intercalated. This division 

 of the system is well seen on the western slopes of the Bamlas 

 heights, north of the Karbasiya gorge, and also in most other sections 

 in the Central Himalayas, wherever the beds below the silurians are 

 exposed. They resemble lithologically the Simla slates (Infra 

 Blaini) and the only fossil traces known from this system have been 

 found in shales in this division. None of these organic remains are 

 more than traces. They are — 



Crinoid (?) stem impressions. 



Bivalve (?) casts and numerous casts of 



Bellerophon s/>. 



The latter occur both in the purplish-pink quartzite and in the 

 shales accompanying it, and rather high up in the sequence of beds 

 of this division. 



In all the Central Himalayan sections through the haimantas from 

 _. . . the Kali river to the Spiti province. I have 



3. Division. * * 



invariably found certain beds which constitute 



the third division. They consist of two zones of very hard quartz 



shales, the lower of which is formed by densely red and pink quartz 



shales, which pass upwards into greenish-grey quartzite and shales, 



( 52 ) 



