42 RANIGANJ COAL FIELD. [ClIAP. IV. § 1. 



Still some denudation does appear to have taken place. Local 



unconformity is seen at Bagonia, where the Grand 

 Local unconformity. 



Trunk Road crosses the Barakar River. Close 



to the old Jain temples, North of the Road, both rocks are seen dipping 



Fig. 4. Section of Rocks neak Jain Temples of Bagonia. 



S 



a. Lower Damiida bed. b. Ironstone shales. 



South by East, at an angle about 10°, but just North of the boundary 

 the dip rolls over sharply to the North for a few yards, and instead 

 of the ironstones being brought in again as they would be, if strictly 

 conformable, the sandstones of the Lower Damudas are overlaid by 

 beds similar to themselves. 



The boundary between the ironstone shales and Lower Damudas 

 South of the Damuda River, and on the extreme South-west of the 

 field, is very peculiar, but unquestionably indicative of unconformity. 

 The runs of conglomeritic sandstone of the lower series form little 

 ridge-like elevations, 20 or 30 feet high, and on following some of 

 these along their strike, they are found to be cut off without a fault, 

 and to abut abruptly against ironstones with the same dip and strike. 

 In one case one of these is far prolonged into the ironstones being 

 interstratified between them, and narrowing gradually from about 

 50 yards in breadth. To the South the ironstones thin out completely ; 

 their lower beds being over-lapped by the higher ones. Nowhere 

 South of the fault, which crosses from North-west to South-east by 

 Chanch and Nuchibad, are they more than a few hundred feet thick. 

 The upper series rests throughout regularly upon them. 



It is probable, that in this place were the shores of the original basin 

 of deposit of the ironstone shales, those shales having been formed of 

 denuded but horizontal beds of the Damuda group. Hence the perfect 



