328 
MANGANESE DEPOSITS OF INDIA : GEOLOGY. [ PaKT II t 
subsequently squeezed out, they tend to change in thickness along the 
strike, with an ultimate thinning out of the mass of rock. Moreover, as 
one -would expect in the case of rocks that have been subjected to great 
tectonic influences, these beds of rock are often folded so as to cause a 
duplication at the surface of the outcropping bands of rock. In some cases, 
such as at Manegaon (page 944), this fact of two outcropping beds of ore 
joining together below the surface has been definitely proved by the work 
carried out in the opening up of the deposit. In others it is to be inferred. 
Thus at the time of my visit in 1904 to Thirori there were apparently 
five distinct outcropping bands of ore. I am told that subsequent work 
at this place has shown that a part of this multiphcity of ore-bands is due 
to the folding of one bed of ore. One cannot say, of course, if a'l the cases 
of two or more parallel ore-bands are due to the folding of a single bed of 
ore. There is no d priori reason why there should not be at any one 
place two or more parallel beds of ore or manganese-sUicate-rock. 
Owing to the fact that these beds of ore and manganese-silicate- rock 
Dip of th- bands of have been folded, they are usually found to dip at 
the gondite series. steep or moderately steep angles, although a small 
dip is also sometimes encountered, especially at the simamit of an anti- 
clinal fold, as at Panchala ; or as at Pachara, where the whole bed of ore 
seems to be nearly horizontal. 
The masses of manganese-bearing rocks and ores often attain great 
^. t dimensions. Thus the Balaghat deposit is If- miles 
Dimensions oi the ^ o r 4 
masses and bands of long; at Manegaon the ore-body is 1| miles long; 
the gondite serie.. ^j^^ ore-band running from Ghondi through Gudma 
and Ukua to Samnapur must be at least 4 miles long ; whilst at Thirori 
the ore-bands can be traced for about 6 miles. If, however, any of the 
lines of deposits represent a continuous run of manganiferous rock be- 
neath the surface then the ore- band must be in some places at least 10 miles 
long, as for example in the continuation of the Thirori ore-band towards 
the north-east through Chaukhandi and Chikmara. In breadth the bands 
of the gondite series and associated ores may be of very small thickness, 
such as 2 or 3 feet as at Wagora. Or they may be of great breadth. Thus 
the true thickness of the ore- band at Mansar is about 50 feet at its 
thickest portion, where it in some places consists almost entirely of ore, 
whilst at Ramdongri the lenticular mass of ore and spessartite-bearing 
rock measures about 1,500 feet across at its greatest width. This 
enormous thickness may, however, be due to the compression together of 
two or more fqldsof the manganese-bearing rocks, although there is no 
evidence to show that such is the case, 
