FAULTS. 10 



v. — Faults and dykes. 



All the faults which have been discovered in the Ramgurh coal- 

 fieldj with but one exception^ seem to belong to 



Three systems. 



one or other of three systems which correspond 

 to those observed in the Raniganj field. 



/. East and West faults. 



The principal fault belonging to this system in the_ Ramgurh field 

 is that which forms the southern boundary. Tracing along this bound- 

 ary from east to west, we find no sign of a fault until we reach the 

 Damoodah close to the Poonoo road ; the rocks seen there on either side 

 of the river indicate that a certain amount of shifting has taken 

 place, the line of fault being identical with the central channel of the 

 river. At this point the fault seems to have exercised its minimum 

 action ; as we go further west, with each step we find higher and higher 

 beds thrown down. Antecedent to this fault occurred the one which, 

 strikes N. by W. : the eflTect of this was to throw down the upper Da- 

 mudds and Ironstones on the east, and thus to bring them within the 

 influence of the former. But for this we should probably have no trace 

 of these beds remaining. To this system may also be referred the fault 

 which lies a short distance to the north of Ramgurh. It is a somewhat 

 interesting feature of this one that where it ceases to form a boundary 

 and runs into the sedimentary rocks it has been considerably deflected 

 from its original direction. It is marked very distinctly by a strong 

 ridge of fault-rock which in some places is from 60 to CO feet wide. 



//. North and South, or sUglitly East of North and West of South faults. 

 An example of this system is the fault forming a portion of the 

 Eastern boundary and cutting off patches of both Barakars and Tal' 

 chxrs. Relatively to the others, there are no data for determining the 

 age of this system, 



( 127 ) 



