Chapter V. — The Lower Vindhyans. 



The lower Vindhyan series occupies two distinct tracts of country j- 

 one in Bundelkund and another in the Sone valley. The first has been 

 already described in the second volume of these Memoirs, and it is with 

 the Sone region that we are particularly concerned in the present report. 



There the series under discussion occupies a narrow sHp of country 

 along both banks of the river, between the Kymore escarpment on one 

 side, beneath the sandstone of which its strata dip, and the slate series 

 and gneissose rocks on the other, on which they rest with a strongly 

 marked unconformity, and out of whose debris their lower beds have been 

 partially formed. The series, although frequently much contorted and 

 disturbed, has throughout a general northerly dip from the older towards 

 the newer rocks, and, as a general rule, the inclination decreases in amount 

 fi'om south to north ; the upper members of the series, are less inclined 

 than the lower. The disappearance of the lower Vindhyans near Bilheri 

 is due to faulting, not to extinction ; but west of this they are only seen 

 once again in some smaU outliers near Kuttungee. Along the upper part 

 of the Nerbudda valley a great fault brings the Eewah group in contact 

 with the metamorphic series, thus sinking the lower Vindhyans out of 

 sight. We cannot, therefore, determine the exact point at which they 

 finally die out, but at the first natural junction seen in the Dhar forest, 

 no trace of the series remains. The probability is, that they do not exist 

 very far west of Kuttungee. 



Along the northern face of the escarpment they are seen occasionally 

 between Sasseram and Chynepur, but disappear completely west of this 

 throughout an interval of more than 200 miles, in which no trace of them 

 is found. After their re-appearance near Tirhowan, they are seen almost 

 uninterruptedly until theii- final extinction to the west. There can be little 

 doubt of their being continuous across this gap, and that their non- 

 appearance is merely due to their never rising above the Gangetic alluvium, 



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