GENERAL GEOLOGY OF THE AREA. 9 



quartz with tourmaline. In others, these two minerals are predomi- 

 nant, the mica and felspar being scarcely dis- 

 Toui'maline granite. , , _ _ . . 



tinguishable. Similar varieties are found on the 



northern slope of this mass, passing gradually into a coarse-grained 



variety of granite, but without the tourmaline. 



Along this section I observed several isolated strips of mica schist, 



much crushed and contorted, and showing signs of 

 Mica schist inclosed. . , . 



having been subjected to further alteration, by heat 



or otherwise ; near the junction with the granitic mass, particles of felspar 



are found disseminated in the mica schist, and give it a gneissic character. 



The strike of the mica schist masses is generally that of the boundaries 



with the metamorphic schists, which also corresponds with the general 



strike of the latter in this region. Probably these masses are connected 



with the main mass of mica schist, and the intrusive granite has simply 



forced its way between the beds of the schists, separating some 



portions of them. 



The parallel section between Maiapur and Pahar Karua is very- 

 similar, excepting that I did not meet with any remains of ciystalline 

 schists in the granitic area. • 



The boundary between the schist and the granite I found about a 



mile north of Maiapur in crossing a small stream south of Deuri. For 



about two miles the path traverses a well-defined plateau of a finer- grained 



variety of granite, which here and there shows 

 Gneissoid granite. . . 



a somewhat gneissic character, but which I cannot 



separate from the main granite area. 



North of the coal-field, between Palgi and Churka, granitic masses 



Area north of the appear again, apparently a continuation of the 



coal-field. granites of the south. In general outline of hills, 



as well as in lithological character of the rock, the granite of this ridge 



is identical with the rocks of the southern area. 

 Lithology. 



Tourmaline granites prevail, and form the main 



mass of the eastern extension of the ridge, sending out long spurs into 



the neighbouring schists. 



( 137 ) 



