118 Records of the Geological Survey of India. [vot,. viii. 
resting upon ironstones, which latter are presumable Barakars. On the east of the valley, 
in the Sukti hill, there is a good section of these rocks. 
Ascending from the village of Bajarmura, which is on red clays and sandstones, the path 
passes over whitish grey sandstones, which might pass lithologically for Barakars ; above 
them near a bear’s cave* is a band of black shales; this is at least 300 feet above the red 
shales of Bajarmura, and must therefore belong to the upper series. 
Above this there were coarse ferruginous sandstones which continued up to the top of 
the hill. On the eastern side of the hill, at Khara, the Barakars extended up the side from 
100 to 150 feet- 
So far as they have been examined, these upper sandstones appear to constitute one 
group which is not susceptible of any natural sub-division. 
V.— Laterite. 
In the course of the preceding pages the occurrence of laterite resting upon the older 
rocks has been occasionally alluded to. It is more particularly abundant on the Talchirs, 
and, as noticed on a previous page, its limits are curiously concurrent with the Talchir—gneiss 
boundary in the eastern part of the field. To the north-east it is often found on gneiss, so 
that its occurrence in one locality in a limited way on the Talchirs only is the more remark¬ 
able. It seems to be chiefly, if not entirely, confined to the lower levels, and I never found 
a trace of it on the higher hills, though in such positions it is commonly met with in Sirguja. 
There is nowhere, so far as I know, a greater thickness of it than about sixty feet. In 
the eastern part of the field it forms wide spreads, which completely conceal the underlying 
rocks. In lithological characters this laterite resembles the laterite of Midnapore and else¬ 
where. 
VI.— Faults and Dykes. 
The character of the south-western boundary having been described in the previous 
pages, little remains to be said, and recapitulation is, perhaps, unnecessary. Although no 
single section can be pointed to as absolutely establishing the faulted nature of this boundary, 
still the general tendency of the observations which have been made is to point in that direc¬ 
tion, while the difference in the character and age of the beds which are successively brought 
into conjunction, and the remarkable straightness of the boundary, are strongly corroborative 
of the same view. 
With this exception there is no evidence of any faulting throughout the area, and most 
of the boundaries have been distinctly seen to be natural. 
Dykes. —But one case of trap also has been met with in the field ; this is at Ivirara- 
ma in the Barakar area, where a dyke is exposed for a few yards. A similar rock is seen at 
Kondaimunda, in the gneiss, and the two may be continuous. It must be noted that there 
is a possibility of this being only the peak of a trap-like metamorphic rock which strikes 
up through the Barakars. Its lithological characters quite favor this possibility. 
VII.—Economic Besottbces. 
The economic resources of this field are—Building materials, Coal and Iron. 
Building materials. —As in other coal-fields containing Damuda rocks, many varieties 
of sandstones occur which would be applicable to building purposes. Hitherto the only 
* Note. —The cave is in a friable bed of slightly ferruginous sandstone, which I noticed was perforated in a 
peculiar manner. On examination each of these perforations, at least those which looked freshest, contained the 
nest, or rather den, of a small spider, while the older ones contained exuvias of spiders. 
It was perfectly obvious that these perforations, which were mostly | of an inch deep, had been made by the 
spiders by patiently removing the friable rock grain by grain. 
