PART II.] 
Blanford: Geolo/jy of Orissa. 
63 
TalghIb, Ongul, and Atmallik.— The TalcMr Coal-field .—Those states comprise 
by far the most interesting geological area in Orissa and its dependencies. The basin of 
sedimentary rocks known as the TalcMr coal-field is surrounded on all sides by metamorphics. 
This basin extends about 70 miles from west by north to east by south, with a general breadth 
of from 15 to 20 miles, its eastern extremity at Karakprasad on the Bramiui river being 
nearly 50 miles north-west of Katak town. Its western limit is not far from Bampiir in 
tho state Badtikol, and it comprises nearly the whole of TalcMr and a considerable portion of 
Ongu.1 and Eadakol, with smaller parts of Bamda, Atmallik, and Denkinal. 
The western half of this field, or more than half, is chiefly occupied by the rocks already 
described as belonging to the Maliadeva group ;* conglomerates and coarse sandstones, which 
form hills of considerable height in a very wild, jungly, and thinly inhabited country. It is 
by no means improbable that the Damuda coal-bearing rocks will hereafter he found in 
portions of this area. Indeed, they have been observed at the village of Patrapada. 
In the extreme west of the field TalcMr beds occur in the upper part of a valley tribu¬ 
tary to the Tikaria near Deinclia, and also near the village of Bampiir in Eadakol. In both 
cases Maliadeva rocks appear to rest directly on them without tho intervention of any 
Damiidas. 
Besides occupying the western part of the field, tho Mahadevas are found in two places 
along the northern boundary, which is formed by a fault of considerable dimensions. One of 
these places is near the villages of Bodaberna and Dercng, where the upper beds occur as 
a narrow belt five or six miles from east to west, their presence being marked by low hills of 
a hard conglomerate. Farther to tho west, they recur in another isolated patch forming tho 
rise called Konjiri hill and its neighbourhood. This hill consists of sandstone capped by 
conglomerate, tho pebbles from which weather out and cover the sides of the hill, concealing 
the sandstone beneath. 
The northern part of the field on which these outliers of the Mahadevas occur is much 
cut up by faults, or, to speak more correctly, by branches of one great fault. These faults are 
in some places marked by a quartzose breccia, containing fragments of sandstone and other 
rocks. The vein of breccia varies iu breadth; at the village of Kerjang, it is so largely 
developed that it forms a hill of considerable height. Between the branches of the fault 
TalcMr beds and metamorphics occur; north of all the faults metamorphics only are 
found. 
The eastern part of the field from near Kerjang on the Tikaria rivor and Koukurai on 
tho Tengria to east of tho Bramini is principally composed of Damuda rocks. These may 
usually be recognised by the occasional occurrence of blue and black shales, the latter carbo¬ 
naceous and sometimes containing coal. The general section of the beds, so far as could be 
made out in a difficult country much obscured by surface clays and jungle, is as follows:— 
1. —Interstratifications of blue and black shale, often very micaceous, with ironstone 
and coarse felspathic sandstone. These are at least 1,500 feet thick. 
2. —Carbonaceous shale and coal, about 150 feet. 
3. —Shales and coarse sandstones, the latter prevailing towards the base; thickness 
doubtful, hut not less than 100 feet. 
* At the period when the Tulehtr coal-field was examined, nothing whatever was known of tho classification of 
rocks which has sitfee been made out by the Geological Survey in the various coal-fields of India. Indeed, one of 
the very first and most important distinctions, that of the Talchlr group below the coal-bearing division, was made 
in this region, as already mentioned. The boundaries of the Maluidcvae and Damudas on the map in the Memoirs, 
Geological Survey of India is merely a rough approximation made from memory after quitting the field. The 
differences of the rocka hud been noted iu the Held, hut their area had not been mapped. 
