26 BALL : GEOLOGY OF THE RAJMEHAL HILLS. 



Barakars and grits intervening between the gneiss and the traps; 

 in the north the above described Damuda rocks alone occupy that 

 position. 



It is, of course, possible that the difference in lithological characters 

 may be due to local causes, and that they were both formed at one and 

 the same period of deposition. It seems not improbable that the rocks 

 of the northern area are the more recent or younger of the two, and 

 may to some extent correspond with the Raniganj beds of the Damuda 

 series. But as we find no trace of the ironstone shale group which is so 

 well developed in the not very distant Raniganj field, and since none of 

 the characteristic Raniganj fossils have been discovered, it would be 

 unsafe to insist upon this view. 



It may be added that these beds are probably of the same age as the 

 Damudas which occur at the foot of the Sikkim Himalayas. Mr. Mallet* 

 is inclined to the opinion that the latter belonged to the Ranigunj group, 

 but fossil evidence in support of this correlation seems to be wanting. 



Though not included within the limits of what we have defined as 

 the Rajmehal hills, the small area of Barakar sandstones which occurs on 

 the banks of the river More may be most conveniently described here. 



North of the village of Tangsiili, which is situated on the banks of 

 the More river, about four miles from Suri, there 



Tangsuli basin. 



is an area of about two square miles occupied by 

 Barakar sandstones, grits and pebble beds, with a few bands of carbona- 

 ceous shale, in which there are flakes and strings of coal one-half to one 

 inch thick. 



These rocks rest in a basin. The maximum dip attained is 12°, but 

 the most common dip is 5° to 6° to south-30°-west. I was unable to dis- 

 cover any trace of bounding faults. The boundaries, especially on the 

 south and east, are, however, much obscured by laterite and alluvium. 



* Memoirs/ Geological Survey of India, Vol. XI, p. 29. 

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