16 GRIESBACH : UAMKOLA AND TATA? ANT COAL-FIELDS. 



Barahars. 

 A considerable thickness of beds, consisting of sandstones, flaggy beds 

 Lithologlcal character ^nd shales, with numerous seams of coal, is found 

 of Barakars. resting on Talchirs everywhere within the limits 



of this area and cropping out beneath beds belonging to upper groups 

 of the lower Gondwanas. Next to the Mahadeva sandstones and shales, 

 they occupy by far the greatest extent of ground, and are readily distin- 

 guishable from the underlying Talchirs, the bound- 

 Boundaries. 



ary with which is very sharp and well marked. 



An unconformity with the Talchirs is at least very probable in some 

 sections. The boundary upwards is not well defined, as the change, 

 both lithologlcal ly and palseontologically considered, is gradual. With 

 the exception of the most eastern development of these beds near 

 Tatapani, the whole area of Barakars is traversed by long faults, 

 especially near and parallel to the great boundary fault of the north- 

 eastern part of the coal-field. The upper series (Mahadevas), occu- 

 pying the centre and main extent of the Gondwana basin, stretches 

 eastward as a long strip, being there faulted against the metamor- 

 phic rocks on the south side. In this field, at least, the Barakars are very 

 distinct from the Talchirs, and lithologically the change is sudden to the 

 fine-grained flags and sandstones with shales, all of which contain Bara- 

 kar fossils. Where the junction is natural, the Barakars dip inwards and 

 apparently conformably under the Mahadevas along with the intermedi- 

 ate Raniganj and Panchet beds. 



The rocks most frequently met with are : — 



1. Sandstones, fine-grained, greyish-yellow, with varieties of white 



and reddish gritty sandstones, often false-bedded, and alter- 

 nating with flaggy micaceous beds. 



2. Micaceous, thin-bedded, grey, shaly or flaggy sandstones, con- 

 j taining carbonaceous matter. 



3. Coal-seams of variable thickness. As yet three distinct bands 



were met with; they occur mostly in the middle of the group, 

 { 144 ) 



