52 BALL : GEOLOGY OP AURUNGA AND HUTAR COAL FIELDS. 



which occur in the neighbourhood of the Daltonganj field, and which 

 have been remarked on by Mr. Hughes. 



The occurrence of calcareous tufi" at Chunhut, on the east of the 



Aurunga field, has already been alluded to when 



describing the crystalline limestones which have 



supplied the material of which it is formed. A similar deposit is found 



in the river Mungurdaha at the foot of a waterfall near Kokaroh. 



Limestones were also found in that neighbourhood. 



The principal, or at least the most noteworthy, deposit of diluvial 

 origin in our area is a red sandy clay, which is directly derived from the 

 Mahadeva sandstones, and forms a belt of unculturable land, much inter- 

 sected by ravines and surrounding the base of the 

 Mahadeva hills. Fallen tabular masses of the 

 ferruginous sandstone occur sometimes enveloped in this deposit ; but 

 more commonly, the result of erosion has been to isolate these masses and 

 leave them perched on columns of stiff clay which often stand out at 

 heights of ten feet or more above the general level of the country. The 

 tabular blocks are frequently from 200 to 300 cubic feet in solid content, 

 and when seen thus perched up above the low brush jungle present a very 



striking appearance. 



Section 9. — Faults. 



The great lines of fracture in our area, of which the faulted junctions 

 afford evidence, are by their compass-bearings resolvable into three 

 o-roups or systems. This arrangement, as will be seen, does not neces- 

 sarily imply synchronism. So classified, they would stand as follows : — 



1. East to west faults. 



2. North of east to south of west faults. 



3. North of west to south of east faults. 



1. East and west system. 



Of east and west faults three have been clearly discriminated by their 



effects in the Aurunga field, and two in the Hutar field. The effect of the 



southern pair in the Aurunga field has been to lower the Mahadevas to the 



level of the Barakars, cutting out all but small remnants of the two 



( 52 ) 



