178 
Records of the Geological Survey of India. 
[vol. x. 
of both series of beds obliquely, and in consequence we find in one place the edges of beds of 
quartzite shales and limestones in opposition to beds of metamorphic rocks, though no actual 
contact is exposed. 
In the neighbourhood of Padampur a considerable section of these rocks is exposed, 
the lowest occurring in the vicinity of Dungri, where the beds form a partial qua-qua versal 
dome which is of a very marked character on the north-west of the hills. 
The lowest beds seen are sandstones forming a central dome. Besting on these in 
the valley, there is an unknown thickness of limestones which dip 15° west under the 
sandstones forming the outer ridge of the hills, where the river changes its course from 
north to east. Above these sandstones again, in the north to south reach, there is another 
bed of limestone which is exposed under the east bank ; overlying this are red sandy beds 
which are exposed near the mouth of the Kailo Elver. Thence up to Padampur, the section 
in the Mahanadi gives an almost unbroken sequence of shaly red sandstones, &c., with about 
100 feet of an externally dove-coloured limestone with numerous veins of calespar. The 
dips at first to west turn to north, and close to Padampnr are inclined to north-east. At 
Padampur there is yet another zone of limestone which contains some strings of galena. 
Under the town the dips are much disturbed, and the rocks are abruptly cut off at the 
boundary. From the preceding it follows that there are in this section, which includes a 
thickness of perhaps as much as 3,500 feet of rocks, four distinct zones of limestone, each 
of which differs lithologically from the others. To the north-west from this the boundary 
runs with that of the Raigarh-Hingir coal-field, metamorphic rocks being occasionally 
interpolated. 
Mr. Medlieott, in his manuscript report of his traverses of the Chlmttisgarh area, has 
given an account of the sections examined by him along the northern, eastern, south-eastern, 
and western boundaries from the Mandla plateau to Sambalpur. The principal forms of 
rocks observed were 1st, strong-bedded quartzite sandstones, “ often coarse and rusty, often 
pure and fine 2nd, “ massive, fine, homogeneous clays often affecting a flat nodular struc¬ 
ture resembling somewhat the splintery clays of the Talchirs. There are also finely laminated 
silicious shales; these are often calcareous, and pass insensibly into finely laminated silicious 
limestones in the manner so common with some of the lower Yindhyan bands of the Son and 
of Bundelkhand. These shales seem also connected with fine flaky beds very hard and com¬ 
pact (porcellanic) on a fresh fracture, but betraying their flakiness by weathering. These 
beds, too, find their exact analogues in the lower Vindhyans 3rd, limestone.—■“ Limestone is 
perhaps the commonest rock at the surface all over the plains of Chhattisgarh. It is seldom 
a pure homogeneous rock, being often flaky and earthy or silicious. Often also the silicious 
matter is distributed in strings or in irregular concentric concretions. 
“ It would seem to be only in the most general way that these several rocks observe any 
order of position. I think all three types may bo observed as bottom rock resting upon the 
metamorphics. But there is a decided preponderance of the sandstones in this position. It 
would seem that the sandstone never attains a considerable thickness, save at or near the 
base of the series. 
“ This variability in the deposits is also a point of similarity with the lower Vindhyans 
and with rocks described by Mr. W. Blanford in the Godavari area. 
“ As the most frequent bottom-rock, the sandstones are seldom seen in force except near 
the boundary, but they are nowhere so much developed as in the south-east, resting on the 
gneiss of the Jonk area and of Sambalpur, and forming ridges running northwards from 
that area.” 
