DAMUDA SERIES. 25 



The paths through Mr. Partridge's tea gardens expose several layers 

 of coal and carbonaceous shale, but I observed none of any considerable 

 thickness. 



In the Sibakhola the Damudas are mostly in a highly altered con- 

 dition, the sandstone being converted into fels- 

 Sibakhola river. 



pathic quartzite with strings of vein quartz 



through it, and the shales into dark grey slate breaking into sharp- 

 edged splinters. No good seams of coal are exposed, although there are 

 several thin ones. 



The Mahanaddi also cuts through several thin layers, and one with 



a minimum thickness of 4 feet; the rest of the. 

 Mahanaddi river. 



outcrop is hidden behind a large boulder. The 

 strata dip mostly to north-north-west at 50° — 80°, and are indurated as 

 in the Sibakhola. 



The Damudas are very badly exposed in the 



Mana river. ' 



Mana, and no good seams of coal are visible. 



Where the central and eastern branches of the Kuhi naddi join, 



there is a cross-fault which shifts the Damiida- 

 Kuhi naddi. 



Tertiary boundary to the north on the east side. 



Ascending the central branch, Damudas, including several thin carbona- 

 ceous layers, are found, dipping towards the north at high angles (60° 

 — 90°) ; a little higher up stream the dip is only 5°, and beyond this on 

 the brow of Latpanchor are Daling slates, having the same inclination. 

 One of the very few cases of igneous intrusion that I have observed 

 amongst the rocks of the Darjiling Himalayas occurs in the Damudas 

 here, which are penetrated by a 7 -feet dyke of micaceous greenstone 

 running vertically to east 10° north — west 10° south. The walls of the 

 dyke are sharply denned, and the Damudas close to it do not show any 

 additional alteration. 



d ( 25 ) 



