ifALLET, VINDHYAN SERIES, 47 



that, in the eastern reg-ion where they are best seen, the three upper mem- 

 bers of the series taken tog-ether present a tolerably uniform thickness ; 

 where the shales are most largely developed the limestone is thinnest, 

 and where the former is absent, the limestone alone maintains the full 

 thickness of the three elsewhere. If there be, however, any disturbance 

 unconformity between the two series, it is so very slight as to be inap- 

 preciable ', but that the lower was more or less denuded is amply proved 

 by the abundant fragments of its strata frequently observed in the lower 

 beds of the upper. Such would seem to indicate a certain break between, 

 which coupled with the sharp line of division which everywhere obtains, 

 and the great chang-e in mineral character and stratigraphy, furnish ample 

 reason for the separation of the two into an upper and a lower series. 

 The strata of the lower are, as a whole, calcareous and argillaceous, of the 

 upper arenaceous and argillaceous, and while much of the upper are thick- 

 bedded and massive, flagginess is a prominently characteristic feature of 

 the lower. The sub-divisions also of the upper are, in the same amount 

 of rock, generally fewer and thicker. In other words, the conditions of 

 deposition change oftener in the -lower during the formation of an equal 

 amount of strata. 



As there is little or no unconformity, the general and often violent 

 disturbances existing in the lower series are of course subsequent to the 

 whole Vindhyan formation, affecting, as they do, the Kymores as well 

 as the beds beneath, and gradually becoming less in the upper portion of 

 the series which was less exposed to the disturbing forces acting from 

 below. The thin-bedded, flaggy nature of the lower Vindhyans no 

 doubt favoured the production of those complicated contortions on a small 

 scale which we find there, and which the massiveness of the Kymore 

 sandstone would forbid. The bends of the latter are on a bolder scale, 

 and it is a remarkable fact that, however crumpled the lower series may 

 be, the strata immediately subjacent to the Kymore sandstone assimilate 

 themselves to it, and are found in even and unbroken layers. 



( 47 ) 



