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



short distances. There are seldom very thick beds of sandstone; thin 

 bands, coarse or fine, but more frequently the former, succeed each 

 other at short distances. Many bands are very regular, and have a 

 considerable horizontal extent ; very little false bedding is observable. 

 Occasionally poor micaceous runs of ironstone are found, but the most 

 characteristic beds of the formation are the white felspathic sandstones 

 and conglomerates, and the thick beds of coal. 



After passing over about 2,000 feet of these rocks in ascend- 

 ing order, a very different class of beds is met with. These are 

 very fine black carbonaceous shales, with numerous runs of clay 

 ironstone (argillaceous carbonate of iron), the latter varying in thick- 

 ness from about 2 feet downwards. A few beds of sandstone occur 

 especially towards the base of the shales. The soil over-lying these 

 beds is usually -strewn with fragments of ironstone, now red from the 

 peroxidation of the iron. No coal has been found associated with this 

 section of the Damuda group. 



These shales, with ironstones, are about 1,200 to 1,500 feet thick, and 



again are over-laid by sandstones, shales, and coal. 



Ironstones and shales. • 



.But the sandstones are generally finer m texture, 



and are massed in beds of greater thickness, than those below the iron- 

 stones; the coarse, white felspathic sandstone, 

 Upper beds. . . 



and conglomerates are almost entirely wanting. 



Nodular hard calcareous bands are frequent ; the coal is more regular, 



of more even quality, and not so frequently a mixture of coal and 



shale, and the seams have a uniform thickness over considerable areas. 



Pebbles are scarcely ever seen, shales are common. 



The questions which arise under these circumstances are, whether 



between the upper and lower series there is any 

 Conformity. . 



well-marked distinction either in conformity or 



in fossil contents, indicating a break ? and whether such a break, if it 



exist, occurs both above and below the ironstone shales, or only in one 



