114 



Section 6. — The Poorna valley with a small poetion of the 



WUEDA YALLEY, being THE SOUTHERN PORTION OF ShEET 54 OF 



THE Indian Atlas. 



This section, as reg-ards area, is one of the largest of all, but its 



geological interest is scarcely in proportion to its 

 General description. . _ , ,, , ^. n .-, 



size. It embraces the greater portion ot the 



districts of East and West Berar and, on its extreme eastern edge 



beyond the "Wnrda, a very small strip of the Nagpoor district in the 



Central Provinces. By far the largest portion of the area is composed 



of the great alluvial plain of the Poorna, bounded on the north by the 



escarpment of the Gawilgurh hiUs, and on the south by the trap rises 



which lead to the Deccan plateau, and which, to the westward, near 



Adjunta, rise much more abruptly than they do farther to the east. 



The only other hills occurring in this tract are a small mass of no great 



height, south-east of Oomrawuttee. 



The alluvial plain of the Poorna, though not equal in length to that 

 of the Nerbudda above Hoshungabad, exceeds it in 

 width, being 40 miles across where broadest.* The 

 boundaries of the alluvium cannot, of com'se, be laid down absolutely, since 

 there is, in all such cases, a gradual passage from a tract completely covered 

 by clays and gravels to one partially covered, in which the underlying 

 rocks begin to appear here and there in stream sections, weUs, &c., and 

 from this again to rocky ground. The boundary has been drawn approxi- 

 mately where rock commences to be seen in the streams and hollows. 



Besides the features of the low countiy, those of the southern 



„ „ ., scarp of the Gawilgurh hills may also be included 

 South scarp of Gawil- ■■• o j 



gurhMlls. i]2 this section. It is along the base of this 



range alone that any rocks of older date than the traps appear within 

 the area of Northern Berar, and the rocks seen amount only to a few 

 isolated inliers in the nqrth-east comer of the Poorna valley. They 



* The greatest breadth of the Nerbudda plain is about 35 miles. 



( 276 ) 



