£ FOOTE : GEOLOGICAL STRUCTURE OF THE EASTERN COAST. 



eastward from the foot of the Eastern Ghats to the Bay of Bengal, and 

 diversified only by scattered hills, or groups of hills, of no real import- 

 ance geographically considered. The drainage is effected in the northern 

 part by the Kistna river, in the southern and central parts by a number 

 of small rivers running mostly in shallow valleys. 



Fiscally the area is divided between the Kistna 1 and Nell ore districts, 

 the northern part belonging to the former, the southern to the latter 

 collectorate. 



The geological structure of this area is almost as simple as the topo- 

 graphical. The western part of the area is occupied 

 Geological structure. 



by a broad band or zone of ancient crystalline 

 rocks belonging to the gneissic series, the eastern part is formed of the 

 marine and fluviatile alluvia, while the intermediate part (speaking 

 roughly) is occupied by a band of patches of sedimentary rocks of two 

 aeres, both older than the alluvial formations. 



Of these three bands the gneissic and the alluvial are by far the most 

 Rocks form three great important in point of extent, the former having 

 zones ' its greatest width in the southern, the latter in the 



northern part of the area. The aggregate area of the other two 

 series of rocks above alluded to, which represent the Lateritic and the 

 Upper Gondwana series, is small when compared with the gneissio 

 and alluvial areas. 



The geology of the Eastern Ghats will not be touched upon in this 

 memoir, as they have already been described in sufficient detail in Mr. 

 King's memoir " on the Kadapa and Karnul rocks/' 3 of which the 

 several ranges of mountains and hills forming the eastern mountain 

 barrier in this part of the peninsula are composed. 



1 The Kistna district, as now constituted, includes the old collectorate of Guntur and 

 the southern part of the old Masulipatam collectorate, the northern taluqs of which were 

 added to the Godavari district. 



2 Memoirs of the Geological Survey of India, Vol. VIII. In this memoir Mr. King 

 has emhodied the results of the examination of the Kadapa and Karnuljrocks by himself, the 

 late Mr. Charles M. Oldham, and Mr. R. B. Foote. 



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