Chap. IX.] faults. 153 



-exist there with a down-throw to the North, for the run of ironstones 

 mapped in the Baniganj series comes in immediately North of the 

 anticlinal, which traverses the country in the same direction as the 

 fault, while many hundreds of feet of rocks intervene to the South of it, 

 and the presence of some displacement is indicated by the peculiar 

 twists and singular dips seen North-east of Manilla. (See p. 120.) 



There are a few other faults, which cannot, with certainty, be referred 

 to any of these three series. Such are the small throws influencing the 

 South-west boundary just North of where it crosses the Grand Trunk 

 Road near Bareghar and Barwa. These are, however, of small amount. 



Some of the most important faults accompany twists in the strike 

 of the rocks. One of these changes of strike occurs about the valley 

 of the main branch of Nunia, where it runs from North to South, from 

 Etiapora to the neighborhood of Asansol. Another occurs near the 

 Barakar, the dip of the rocks changing from S. S. E. to S. S. W. in 

 each case. It is probable that both phenomena were due to the same 

 disturbing causes. 



The age of the faults, as a mass, has already been shown to have been 

 „ , probably in the time which intervened between 



Age of faults. 



the Panchet and Rajmahal periods. No addi- 

 tional evidence of importance exists beyond that afforded by the dykes. 

 All three series throw every rock from the Panchets downwards — their 

 effect upon the Panchet grits is unknown ; but there is no doubt that 

 they were thrown by the East and West fault forming the South boun- 

 dary of the field, as no outliers of them are known to exist beyond. 



There appear to have been faults in the Talchir rocks previously to 

 the formation of the Damudas, but their direction has not been clearly 

 made out. 



u 



