NERBUDDA DISTRICT. 241 



part of them. These lines may all be distinctly seen to be faulted, and 

 in every case where the newer beds are seen to rest on the old crystalline 

 rocks, we find that the junction is always within, and never outside the 

 general line of the fault. 



The Vindhyan Fault Boundary. — In the first pages of this report the 

 general aspect of the Vindhyan boundary has been described. This 

 scarp forms certainly the most striking feature in the scenery of this 

 part of Central India, and is most important considered as a geological 

 phenomenon. 



The first thing to strike the observer, and which may be noticed even 



General aspect rectili- b ? ins P e c tin g the accompanying maps, is the well 

 near * preserved rectilinear direction of the boundary 



line. The great escarpment is, as has been stated, varied along this line, 

 by many projecting promontories, and receding bays ; and the bounda- 

 ries of the alluvium, traced on our maps, somewhat disguise the true 

 boundary of the Vindhyan sandstones. If this were shewn, it would 

 appear that, though the escarpment has been often cut back into bays, 

 yet that the true boundary of the rocks beneath would much more near- 

 ly coincide with the line joining the opposite bluffs of such bays, than 

 with the alluvium boundary which follows the contours of the present 

 surface. Moreover the deviations from the rectilinear direction are often 

 seen to be curiously rectilinear in detail; that is, the approximately 

 straight line of the general boundary is made up of shorter straight lines, 

 and not, as might be conceived from an inspection of the map, of the 

 curved outlines of the boundary of the rocks as determined relatively 

 to the alluvium. 



Little less striking than this rectilinear feature, it will be noticed that 



No Vindhyans on the the boundai T is, as far as our area is concerned 



south of the valley, absolute and complete, that is, no vestige of the 



Vindhyan rocks is known to occur south of it. All those rocks from 



the Talcheer up, which are so frequently seen, on the south of the 



T 



