DtJBRAJPDR GROUP. 53 



From Kharmatand the grits extend northwards, skirting the hills 



«.,'-. to the Jumri valley, beyond which occurs the third 



Overlap of trap on J J 



gneiss instance which we have to record of the overlap 



of the trap on to the gneiss. 



To what extent the rocks of this group may exist north of this is 



uncertain. It is quite possible that some of the hills which are within 



„ ,, . the Barakar area are partially formed of them. I 



Further extension r J 



northwards uncertain. jj ave a i rea dy stated that Mr. Blanford considered 

 a strong lithological resemblance to exist between certain white beds on 

 Lohundia and the Palaozamia beds south of the Brahmini. 



The relationship existing between the rocks of the Dubrajpur and 



^ , Barakar groups, respective^, are sometimes ob- 

 Eelations between Bara- . 



kars and Dubrajpurs. scure, but occasionally the lower beds shew signs oi 

 having been disturbed to a much greater extent than are the upper, and 

 the cases of overlap are numerous and of such a character as to leave no 

 doubt that an interval in which denudation was active elapsed between 

 the two periods. 



That the Dub raj pur rocks, too, are separable by a distinct interva 

 from the trap and intertrappeans is also abundantly manifest from the 

 cases of overlap and the evidence of pre-trappean denudation which 

 occurs in the Brahmini valley and at Kharmatand as has been described 

 above. 



We are, therefore, justified in regarding these rocks as belonging to 

 a distinct period when compared with the Barakars which underlie them. 

 At the same time it must be borne in mind that we have, in the northern 

 part of the area, Damuda rocks of a distinct character from, and probably 

 younger than, the more typical Barakar rocks of the south. If this sup- 

 position as regards their age be correct, then they in all probability were 

 deposited locally in the north while denudation was taking place in the 



south. 



( 207 ) 



