78 MALLET, VINDHYAN SERIES. 



a thickness of close on 6,000, In the Dhar Forest, their most westerly 

 limit in the Nerbudda Valley, they are supposed not to fall short of 

 10,000 or nearly two miles. A fine section of this immense accumulation 

 may be studied along the course of the river, which winds through a 

 rocky channel, often bounded by precipitous sides, where the distm-bances 

 which have afiected the Yindhyans are clearly exhibited. Those dis- 

 turbances are often violent, shifting the rocks and twisting them up 

 vertically, but, as a whole, the strata of the Dhar forest area form a 

 shallow synclinal, those in the eastern part having a general westerly 

 inclination and vice versa. The highest beds therefore are met with in 

 the centre, and these bear a sufficiently strong resemblance to the lower 

 Bundairs to render it not impossible that they should be referred to that 

 group. If such be really the case, since they are found close to the 

 fault, which brings the Vindhyans against the Bijawurs north-west of 

 Burwai, it shows what an enormous throw that fault must have ; equal 

 to the entire thickness of the Bewahs. . , 



Perhaps not unconnected with the disturbed state of the rocks in 

 this region is the fact of its being the only one yet known where the 

 Vindhyans have undergone the intrusion of igneous matter. Two or 

 three trap dykes are observable in the bed of the Nerbudda, and a very 

 large one occurs near the centre of the area, the course of which is 

 marked by an elevated ridge. No doubt a closer examination would 

 detect many more. 



The Bewahs are more altered in the Dhar forest than anywhere to 

 the east, the sandstone being so much vitrified as to pass frequently 

 almost or entirely into quartzite. Thick shaly bands sometimes occur,* 

 mostly quartzitie or silicious but sometimes more or less earthy, and the 



* One of such being those beds at Pullassi formerly supposed to represent the 

 Sub-Kymore, or lower Vindhyan series (Vol. II, p. 139) ; as previously stated, however, thafe 

 series is absent in the Dhar forest, not extending fui-ther west than KuttungL 



( 78 ) 



