PART 4.] 
Foole: Geology of Norik Arcot Dintrict. 
199 
the beds forming the south-western part of the Sattavedu hills. Liko these they 
have a more or less easterly dip, and disappear under the lateritic beds, which lap 
round the eastern foot of the hills, and which, together Avith the great talus 
which has accumulated on the base of the slopes, completely obscure all the rela¬ 
tions between the lower’ and upper rocks, l^o fossils were found in the Alikur 
hills. The hard beds occupy only about a third of the area of the Alikur out¬ 
crop, the remainder being formed of the soft bods assumed to belong to the Sri- 
permatur group, and which, as already mentioned, appear to underlie the hard 
beds conformably. No section was found showing these two dissimilar series in 
contact where they approach each other in the centre of the Alikur hill gi’oup, 
but as far as the rounded outlines of the hills at that point serve to guide the eye, 
there is an undoubted dip of the softer beds under the hard conglomerate. No 
sign of any fault could be traced, but from the peculiar nature of the case, a fault 
of great importance might well exist, and yet be completely hidden by the vast 
quantity of debris and talus which everywhere almost cumber the surface even of 
steep slopes. The nearest visible approach of the two series is a short narrow 
east and Avest ridge abutting at right angles against the hard basement conglo¬ 
merate of the Sattavedu series, Avhich here forms a conspicuous north and south 
ridge parallel with several of similar character further east, each representing a 
great conglomerate bed. The valleys running down north and south from the 
cross ridge are the two principal ones in the central mass of the hills, and their 
depth, which is considerable, is due to the greater softness of the imderlying 
beds as compared with the overlying set. 
The soft beds so frequently named consist of conglomerates, gritty clays, and 
shales of white or gi’ey colors. Even the coarsest conglomerates at the very base 
of the series are uncompacted and soft, the enclosed pebbles and boulders of 
gneiss and quartzite merely lying embedded in very friable more or less clayey 
grit consisting of quartzose debris of gneissic origin. The slopes of the hills 
composed of such soft beds are deeply covered by debris, while but fcAV of the 
rain gullies descending from higher slopes penetrate sufficiently to expose the 
rocks in situ. The Naikenpalem hills, which occupy the southern part of the 
Alikur area, consist, as far as seen, entirely of the soft beds Avhich have trended 
round from a north and south strike in the Alikur hills to one running west- 
north-west to east-south-east. 
Numerous plant remains Avere obtained from a clay bod exposed in one of the 
principal rain gully sections east of Naikenpalem village. Amongst the remains 
were parts of Tesniopteris, Dictyozamites, Ptilopkyllum, &c., all characteristic 
Rajmahal plants. Unfortunately the specimens, which are beautifully distinct 
when freshly extracted, are utterly ruined by the shrinkage of the wet clay as it 
dries. 
Near the village of Naikenpalem the basement bed includes enormous masses 
Included masses of conglomeratic quartzite, some of them from 800 to 
quartzite. 1,000 cubic feet in bulk; those are very probably relics of 
the basement bed of the Kadapa series, which is so generally represented a few 
miles to the north-west and north in the great scarps of the Nagari mountain and 
the Ramagiri. These great quartzite masses are not seen resting actually on the 
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