GEOLOGY. 



In walking from Hazaribagh. to Ranchi clay s and carboni- 

 ferous shales are met with at about the 21st mile which 

 belong to the Damnda series of the Gondwana system. These 

 rocks are more or less evident all down the Damnda valley, 

 and contain the coal-fields of Ramgarh and Karanpnr in 

 Hazaribagh. The Gondwana system is also well developed 

 in tne Earakar valley, and tilted beds of sandstone north of 

 Bagoda, as well as the micaceous shales composing some of 

 the small hills north of the Barakar, possibly belong to it. 

 The Gondwana system is important, as the Damnda series 

 bears the coal measures of Raniganj (in Bardwan, but close to 

 Chota Nagpnr), Jheria (in the Damnda valley, Manbhnm), 

 Giridih (Barakar valley, Hazaribagh), Daltonganj (Palamau), 

 and several less important fields. The formation is also 

 interesting from the occurrence cf similar coal-bearing 

 Damnda beds in Sikkim and Bhotan, indicating a continuity 

 of the land in that direction when sea occupied the greater 

 part of the Indo-Gangetic plain and Himalayan area, In the 

 subsequent elevation of the land we may assume the moun- 

 tains of Chota Nagpnr not only to have been on a far grander 

 scale but to have borne much the same flora as their extension 

 into Assam and adjacent areas. As these conditions are 

 believed to have existed right up to tertiary times, the 

 presence of so many eastern Himalayan and Malayan types in 

 Chota Nagpnr might thus be accounted for. Ball states that 

 the outlying hills and prolongations of the Chota Nagpnr 

 plateau owe their character and origin to denudation modified 

 only by the inclination of the beds, and not to local or special 

 upheavals. "That the general level of Manbhum corre- 

 sponded to the rest of Chota Nagpur in times previous to 

 the scooping out of the Damuda and other valleys, and the 

 deposition of the coal measures and associated rocks, is 

 proved, not only by the scattered hills, a few of which 

 approach in elevation that of the Chota Nagpur plateau,but by 

 the fact that the Subarnareka and many of its smaller tribu- 

 taries pass at right angles through gorges cut deep 

 through hard ranges of trap, quartzite, and tough mica 



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