48 KING : NELLORE PORTION OF THE CARNATIC. 



debris on this side of the bills. Their strike now trends in to the Veli- 

 gondaSj from which, however, they must be cut off by faults, there being 

 no outcrop of bottom beds corresponding- to them in the range. The 

 Udayagiri plateau may be a portion of the same band, but even so, it is 

 detached from it by a wide interval and by tremendous displacements, 

 being, as it is, a denuded cap of nearly flat strata at an elevation of about 

 &,500 feet over the level of any quartzite boundary to the south or west. 

 Mr. Oldham wrote of these ridges and hills north of the Penner, and 

 some of his notes are particularly interesting as giving instances of un- 

 conformity of the quartzites on the gneiss, even in the Dargadevi Konda, 

 the rocks of which are undoubtedly continued in the Kaluvaya ridge. 

 He also shows that these quartzites are overlying not only the schistose 

 gneiss, but that they extended on to the massive gneiss, a narrow strip 

 of which crops out here. 



The Veligondas themselves consist for the most part of quartzites 



The Cuddapahs in the (conglomerates and sandstones of all kinds and 

 Vehgonda range. colours) in great thicknesses associated with fewer 



and thinner bands of clay-slates, micaceous and talcose slates, and still 

 fewer schistose beds, all of which are dipping generally to the eastward, 

 but with many undulations and some reduplication. The eastern edge of 

 the range is fringed for the greater part of its length by a talus of debris 



Faulted against the °^ g 00 & width, which conceals the main eastern 

 g neiss - boundary of the Cuddapah formation, though the 



newer and older rocks are at times traceable to within very close proximity. 

 In all such cases, however, the indications are that the boundary must 

 be an abrupt one and faulted to a great extent. The beds dip constantly 

 at high angles at the gneiss and have a crushed appearance, and the 

 serial order of the rock groups seems to justify the conclusion that there 

 must be great thicknesses of quartzites and slates faulted immediately 

 west of and below the level of the adjacent gneiss. 



The boundaries striking westward and northward from Yarapet, at 

 the southern end of the range, are certainly faulted, the downthrow inside 

 these lines being at least 1,000 feet at the village, whence it decreased 

 ( 156 ) 



