150 RANIGANJ COAL FIELD. [CHAP. IX. 



unfortunate, for no question can be of greater importance to the miner 

 than to know, by the help of a geological map, where he may expect to 

 meet with faults or " troubles," and if he intends to mine beyond them, 

 in which direction is the down-throw. 



Even some of the largest and most important faults in the field 

 cannot be traced for any great distance into the sedimentary rocks. 

 The difficulty of following them has induced a strong belief that they 

 are more numerous, and the throw greater, in the Lower Damudas and 

 Talchirs, than in the Raniganj beds and Panchets. This seems espe- 

 cially the case with, the numerous faults running about North 20° 

 East in the neighborhood of Jamiari, none of which can be traced to 

 have any effect upon the ironstone shales, the boundary of which, how- 

 ever, is by no means clearly seen in the places where it should be inter- 

 sected by the faults. 



The greater number of the dislocations occurring in the Raniganj 



area may be divided into three series of parallel, 

 Three principal series. 



or nearly parallel, faults. 



I. A series running about West 10° — 20° North: to this belongs the 

 great fault forming the Southern boundary of the field. One other 

 fault may also be referred to it, viz. that forming the Northern 

 boundary of the field from the Adjai, near Daskiara, North of Etiapora, 

 to beyond Birkunti. It is extremely probable that this series of faults 

 may not be entirely the effect of one period of disturbance, but the 

 accumulated dislocations of many movements at various times. It 

 belongs to a series which has enormously influenced the rocks of 

 Bengal and Eastern India, and the throws are frequently, as in the 

 present instance, of gigantic dimensions. 



There is perhaps no example on record in which the throw of a large 

 fault had been determined with greater accuracy 



Enormous fault ou 



South boundary. than in the case of that bounding the Haniganj 



field to the South. The steady dip of beds, whose out-crop extends in 



