RECORDS 
OF THE 
GEOLOGICAL SURVEY OF INDIA. 
Part 4.] 1877. [November. 
On the Geology of the Mahanadi Basin and its Vicinity, by V. Ball, M.A.,F.G.S., 
Geological Survey of India. 
A detailed description of the geology of the extensive area included in the accompany¬ 
ing map, even to the limited extent to which the details of a large portion of it are known, 
would occupy a very much greater space than is available for the purpose in these pages. 
In the appendix below will be found a list of papers which describe the coal-fields and 
certain other parts of the area which have been made the objects of special examination. 
This account is intended’ mainly to afford a general sketch of the geological features of 
those portions of the area of which hitherto there has been no published description what¬ 
ever. The data available for this purpose are derived firstly, from manuscript accounts 
of traverses of the Chhattisgarh basin made by Mr. Medlicott in 1866-67 and by Mr. 
W. T. Blau ford in 1863-70 ; secondly, from my own observations made during the past 
and previous seasons. 
The geographical tiact which is coloured geologically on the map embraces an area of 
about 50,000 square miles, in which the following British Districts and Native States are 
situated: Cuttack, with portions of the Garjat states of Orissa; Gangpur, and Udaipur and 
other minor states of the Chutia Nagpur Division ; Samhalpur, with portions of its Garjat 
states of Sonpur, Patna, Borosambar, Phuljhar, Raigarh, and Kalahandi; the Jaipur State 
under Vizagapatam ; the Bust.ar State under Sironcha; Ivariul or Kariar, Bindra-Nowagarb, 
and various other states of the Raipur District. In other words, the area includes portions 
of the south-west frontier of Bengal, nearly the whole of Orissa, a small portion of the 
northern frontier of Madras, and a considerable portion of the most eastern districts of the 
Central Provinces. 
Physical Featuees. —On a map of so small a scale as that which accompanies this 
report, it would be impossible to effectively delineate the various groups of hills and plateaux, 
marked and extensive as some of them are. It has therefore been thought better to omit 
altogether the inadequate hill shading of the original map from which this edition has heeu 
produced, thereby securing greater clearness for the names and geological boundaries. 
But it will be well for the reader to bear in mind that throughout about two-thirds of the 
whole area broken hilly ground prevails. The first great group of hills to be mentioned 
forms a section of the Eastern Ghats stretching in breadth from the neighbourhood of Berham- 
pur, the Chilka Lake, and Cuttack, for a distance of about 130 miles westward to the valley 
of the Tel River in Kalahandi. North of the Mahanadi, this broad zone continues through 
Keonjar and Moharbanj, losing itself on the east in the plains of Midnapur and Singlibhum, 
but maintaining its western branch strongly through Lohardugga and Hazaribagh. 
