156 FOOTE : GEOLOGY OF THE BELLARY DISTRICT. 



Dharwar system were supposed to have been upheaved, contorted and 

 riven in every direction. This was the view advocated by Newbold 

 in his Summary of the Geology of India and reproduced by Dr. Carter 

 in his Summary given in the Geological Papers on Western India. 



That such is not the case I have already pointed out when 

 dealing with the contact of the Dharwarsand the granite to the north- 

 ward of Daroji (p. 52) where the veins, seen traversing the trappoids 

 and hornblendic schists of the extension of the Copper Mountain 

 synclinal, are not branches of a granitoid mass penetrating into the 

 Dharwar rocks, but veins of a far younger pegmatite, a rock differing 

 much from the granite petrographically and as much irruptive in it 

 as it is in the adjoining schists. Newbold's comparison of the well- 

 known remarkable show of granite veins at Cape Wrath with these 

 veins north of Daroji is simply unintelligible. 



The most noteworthy example of the pegmatite veins is that to be 

 ... seen on the right bank of the Tungabhadra 



Pegmatite veins in _ ° 



the bed of the Tunga- where an extension of the Sandur synclinal fold 



bhadra, W. of Hospet. . . 



crosses the river. The pegmatite veins here 

 form a group of four, of which two lie close to the western side of 

 the synclinal, a third crosses from the village of Mellapur to Honnur 

 Malai (Honoor Mully) on the northern bank, and the fourth, which 

 lies about half a mile to the north-east of No. 3, crosses the southern 

 branch of the river to the island in the middle of the stream beyond 

 which its course was not visible from the south bank. The river is 

 not fordable even at low water and no boats were to be obtained 

 by which to cross, so I had to leave the northern ends of the veins 

 unexamined. 



These veins differ from the ordinary pegmatites met with in the 

 granitoid region in having the quartz and felspar ingredients in very 

 equal proportions and in being of fairly uniform texture throughout. 



Where not discoloured ("black-leaded ") by the action of the 



river-current the reddish pegmatite makes a strong contrast with 



the dark, almost black, trappoid which forms the principal mass of 



the Dharwars crossing the river. The veins have been curiously and 



( 156 ) 



