20 BALL: GEOLOGY OF THE EA.TMEHA-L HILLS. 



Beyoiid the Mohwagarhi hill, the metamorphic rocks occupy an 

 irregular-shaped area of about five square miles in the mouth of the 

 Bansloi valley, otherwise known as the Pachwara pass. Thence north- 

 wards they follow the much indented outline of the 1 hills until they 

 sweep eastwards into the valley of the Gumani or Chuperbhita pass. 

 Here, too, occur three inliers of gneiss surrounded by sedimentary or 

 trappean rocks. From the Chuperbhita pass the- boundary passes close 

 to Kurmatand, and thence skirting 1 the coal-measures which crap out from 

 beneath the trap hills of that part of the area, it passes round the Gun- 

 desuri hill, of which we shall have to speak again hereafter, and a short 

 distance further north, the metamorphic rocks become covered «sp hy the 

 alluvium. 



To the east of the localities mentioned above no metamorphic rocks 

 are anywhere exposed throughout the area occupied by the hills. 



In the following pages the cases of overlap of the Talchirs by 

 Damudas, and of them again by the Dubrajpur 



Overlap. 



grits, will be found duly enumerated. From this 

 cause the metamorphic rocks are successively overlaid at different places 

 by the different sedimentary formations, and not only by them, as three 

 cases at least occur where the trap rests immediately on gneiss without 

 the intervention of any other rocks. 



Any full account of these metamorphic rocks would necessarily 

 involve their being followed into the west far beyond the limits set to 

 this report, so that nothing more than the above brief notice of them 

 can be given at present. I shall, therefore, pass on to describe the next 

 succeeding formation which occurs in the area. 



( m ) 



