105 Fl^miOU : OKOT-OnV and coal RESOTTRCES OE KOREA, c. r. 
After referring to the Aravallis, it is stated : — 
" At the sumo time another zone of contortion w as formed runninp; along 
the south side of the Son and Narbada valleys, which was prol)al)ly marked 
by a range of mountains or hills, not rising to the same height or importance 
as the Aravallis. and hearing mueli the same relation to them iis the hills 
west of the Indus alluvial plain do to the Himalayas of the present day." 
According to the division instituted by Sir Thomas H. Holland, 
in favour of which tlic evidence seems conclusive, the ancient 
non-fossiliferous rocks of the Peninsula of India may be grouped 
into two main divisions, the Archajan and Purana, of which the 
younger Purana rocks have as a rule suffered practically no meta- 
morphism and dip at gentle angles, whilst the Archaean rocks on 
which they rest have frequently been subjected to intense meta- 
morphism, folded together, and forced to dip at high angles, so 
that there is a vast unconformity, termed by Holland the great 
Eparchajan unconformity, between the whole congeries of rock 
systems grouped under the term iVrchsean and the systems included 
under the term Purana. It is difficult, therefore, to accept 
the suggestion that the formation of the earliest Satpura 
range is to be ascribed to the close of the Cuddapah period. The 
gneisses and metamorphosed Dharwar sediments must have suffered 
their principal folding prior to the Eparchaean interval. In addition 
to these folded gneisses and schists, an important constituent part 
of the Satpura core consists of the various unfoliated or but sHghtly 
foliated granites so abundant in Chhindwara, Seoni, Mandla, and 
Balaghat, on the west side of the Maikal range (of which Amar- 
kantak forms one of the highest peaks), and in Pendra and Korea 
on the east side of this range. There is no reason for regarding 
these granites as of any but Archaean age, and we may explain 
their intrusive relations with regard to the associated gneisses and 
schists, and also their comparative freedom from foliation, on the 
hypothesis that their intrusion at the close of the Archaean period 
was the cause of the upheaval of the Satpuras as a mountain range 
of which we now see the denuded core ; or at least that the in- 
trusion of these granites was intimately bound up with the tectonic 
movements to which the Satpuras owed their elevation. 
These ideas are put forward on the supposition that there is 
an intimate relationship between the folding of the Archaean 
rocks constituting the present Satpura core and the formation 
oi the Satpuras as a mountain range, this being the idea expressed 
in the Manual as already quoted, the portion to which I take 
