<54i BALL: GEOLOGY OP AUKUNGA AND HUTAE COAL FIELDS. 



the village of Seruk. To the north of the field at Balu-naggar there 

 are several hills connected with the higher regions bordering the valley, 

 which are formed chiefly of thin-bedded hornblendic gneisses, with veins 

 of coarsely crystalline pink granite and pegmatite, and capped by 

 Barakar pebble conglomerates, as will be described on a future page. In 

 the valley of the Tataka^ to the west of this, the rocks consist chiefly of 

 gneiss with pegmatite and epidote veins, but hornblendic and granitic 

 rocks also occur. The general strike of these rocks is the same as that 

 of the bounding face of the plateau and of the subordinate ranges, being 

 about east-north-east to west-south-west. 



A very peculiar form of gneiss, which I at first mistook for indurated 



„ , ,., . Barakar sandstone, occurs in that portion of the 

 Sandstone-like gneiss. 



Sukri which lies to the north-west of Toobed. 

 Foliation is obscure, and the face of the rock shews lenticular masses and 

 strings of coarsely granular structure, which closely simulate the irregular 

 texture of certain Barakar sandstones. 



These rocks are cut into a deep gorge by the Sukri and are in places 



_ , eroded into pot holes of considerable dimensions. 



Pot-holes. ^ 



The rocks which surround the remainder of the 



western extension of the Aurunga field consist mainly of varieties of 

 granitic and hornblendic gneiss, about which there is nothing of import- 

 ance to be recorded. 



On the southern side of the field the metamorphic rocks have a 



generally similar character. It is noteworthy that 

 Calcareous gneiss. . . . , ,. 



in the Aurunga river section, a short distance north 



of the Daltonganj and Ranchi road near the village of Bhoosor, the 

 gneisses are somewhat calcareous, and that they are on about the position 

 of the south-west continuation of the direction of strike of the above- 

 described limestones of Chunhut. 



Besides the inlier already mentioned north-west of Seruk, there are 

 several other localities where metamorphic rocks 



Inlicrs 



occur inside the boundary. In the Sukri section 

 ( 34 ) 



