Department of Geology, India
*Corresponding author:Banerji DC, Department of Geology, India
Submission: September 12, 2020;Published: November 03, 2020
Manganese deposits of Balaghat belt of Madhya Pradesh, India, occur as shear parallel quartz-manganese
interlayers restricted within the mylonite zones of the area. The interlayered ore bodies, along with the
shear planes, maintain a co-axial, non-coplanar relationship to the S1 schistosity of the country rock.
They also exhibit folding along S2 and S3 axial trends and attain a sinuous map pattern. These ore bodies
also show widespread felspathization of the wall rocks and pneumatolytic activity along their periphery,
resulting in the development of tourmaline, apatite, chlorite, fibrolite bearing quartz-mica schists/
gneisses. Dimensional orientation of the constituents of the ore bodies along ‘S’ and ‘C’ planes of the
mylonites is characteristic with all the deposits, indicating ductile to brittle ductile movement along these
mylonites.
It is envisaged that the rocks of the area, belonging to Sausar Group of metamorphites, were subjected
to shearing during late D1 deformation. These shear zones were then occupied by hydrothermal bodies
related to late D1 pink magmatism. These hydrothermal bodies were either rich in residual manganese,
or scavenged manganese oxides from the manganese silicates of the country rock. The calcium rich
manganese silicates ‘Gondites’ are possibly produced by interaction between the felspathic components
of the hydrothermal bodies with the manganese oxides and the randomly occurring calc-silicate enclaves
of biotite gneiss. The hydrothermal hypothesis towards the origin of manganese explains satisfactorily
the anomalous occurrence of high temperature oxide ores with intergrowth textures in the low
temperature region of Sausar metamorphites. It also explains the absence of other members of the Sausar
metamorphites from the so called ‘narrow furrows of deposition’ as advocated for the biotite gneiss
hosted manganese deposits
Keywords: Mylonites; Pink magmatism; Hydrothermal emplacements; Boron metasomatism;Griesening; Gondite.