6 
Records of the Geological /Surrey of India. 
[vol. II. 
The area of these rocks, from the Kistnah river down to Naggery Nose,* then- 
southernmost extremity, is about 13,500 square miles. The greatest thickness of each for¬ 
mation, as at present known, is:— Kubnools, 1,200 feet; Kuddapahs, 21,000 feet. 
The most interesting feature about these formations is that they are most probably 
representatives of the great VlSDHYAN series of Indian rocks. This conclusion has been 
arrived at from careful comparisons of typical rock-specimens from either series, and of the 
recorded observations made during the surveys of each. The Vindhyans have now been 
traced as far south as the Godavery river, where it traverses the district bearing its name ; 
and here they are so lithologically and stratigraphic-ally like the Kuddapahs and Kubnools 
on the Kistnah river, not very- far south, that there hardly remains a doubt as to the identity 
of the one with the other. 
The history of the Kuddapahs is still to be thoroughly worked out; and on this 
account, the present sketch will he more directly confined to a description of the Kubnools. 
There are, however, some well-marked and clearly made out features of the Kuddapahs 
which may in the mean time he adverted to. 
Both formations agree in this, that they are largely made up of buartzites, while 
limestones are sparingly developed in one and extensively in the other; but the Kuddapahs 
are distiuot in. showing strong groups of clay-slates, with one of which it may be necessary 
eventually to include the trap-flows and their associates referred to above. 
Supposing at present that all the quartzites, slates, &c., not included in the following 
description of the Kubnools, may be considered as of the Kuddapah Eobmation, 
it is then possible to give an idea of their locality in the great area of country occupied 
by this formation. 
The Goolcheroo hill-ranges south of Kuddapah, and their extension south-eastward 
down to Triputty and the Naggery hills, are made up of quartzite sandstones and conglo¬ 
merates ; while rocks of the same kind with bands of shite go to form the long range of the 
Eastern Ghats-pr Yellacondas lying between the Kuddapah and Nellore districts. The 
country south-east of Kuddapah, that is Ontaniitta, Chitwail, Pooluinpet, &c., 
withimthese mountain ranges, and that due north of it;—■fTullamullays, Budwail and 
Cumbuin, up to the Kistnah river, are also made up of like rocks of the same formation. 
The Gundicottah range of hills, north-west of Kuddapah, is likewise of these old 
quartzites, and the parallel ridges and valleys between that range and the Bellary district to 
the west, with their extensions right up to Jaggaruat-Oonda (hill), a few miles south of 
Kurnool, are of quartzites, slates and traps. 
These older rocks are interesting as being traversed, at rare intervals, by veins and 
strings of copper and lead ores, accounts of which have from time to time been given by 
writers on the resources of Kurnool and Kuddapah. Copper ore occurs very sparingly ; in 
fact, there are only traces of it, hut the sulphide of lead is more abundant. The workings 
for both were abandoned years ago; a state of things perhaps due to the difficulties 
in the way of living at, and working the mines, rather than to a failure in the ore. 
Traces of these ores are also known in the older crystallines or gneiss, of the remainder of 
the districts. 
With such a brief account of what is at present known of them, the Kuddapahs may 
be left for future description. 
Kubnools. 
This formation unfolds itself as a double series of groups of limestones and quartzites; 
the lowest beds of all being quartzites, as thus, in descending order:— 
1. Limestone group 
3. Quartzite group 
3. Limestone group 
•1, Quartzite group 
...{ 
...{ 
-{ 
...{ 
a. Calcareous shales. 
b. Limestones. 
a. Pinnacled beds. 
b. Plateau beds. 
a. Non-calcareous shales. 
b. Limestones. 
a. Massive beds. 
b, Pecs (containing diamond gangue). 
A peak of the Naggery range, about -iO miles W. N. W. of Madras. 
