80 GEOLOGY OF THE SON VALLEY, ETC. 



sometimes observed. In other places we find no more trace of either 

 pyroxene or amphibole, only large crystals of epidote surrounded 

 by chlorite. 



The characters of the ground mass are like those observed in the 

 fragments that constitute yV/^. The pyroxene has combined with 

 some of the felspar substance producing a closely matted mass of 

 minute actinolitic crystals which even spread into the porphyritic 

 felspars and obliterate the sharpness of their outlines. The flow 

 structure is well indicated by aggregates and strings of ilmenite and 

 leucoxene. 



North of this rock comes a calcareous schist of the same colour 

 (specimen -*VV). It is a limestone containing a 



Metamorphosed tuffs. . - . . , . , 



considerable proportion of chlorite and epidote. 

 These secondary minerals must have been derived from materials 

 similar to some of those contained in the volcanic rocks just 

 described. We may regard these rocks therefore as sediments con- 

 sisting of finely divided eruptive material, mingled with the calcite 

 which may be itself of volcanic origin. 



Further north these strata become interbedded with saccharoid 

 limestones, and then the section is concealed. 



I will now refer again to the list of strata given on page 158, as 

 occurring in the neighbourhood of a hill marked 



Rocks near Belawa peak. , . _ , , ,, „. . 



on the map as "Belawa peak.' lhe rocks 

 belong to the same band as those described from Girwi, but the 

 series has acquired more importance and contains some interesting 

 rocks which in the Girwi section are absent or imperfectly exposed. 



The most southern rocks belonging to the band G, are analogous 

 to those just described from Girwi; they contain the same dark 

 chlorite schist and the limestone bands. Further north they are 

 interbandod with beds of an igneous nature. These 0^1 account of 

 their superior hardness often give rise to hili ranges : such is the case 

 with specimen 7 y ¥ , collected at the summit of the peak occurring 

 north of Jagraowa This rock presents some curious peculiarities. 

 It shows very distinctly in the hand-specimen the long prismatic 

 ( 3o ) 



