Reinterpretation of Stratigraphy and Structure of Sausar Group in Ramtek-Mansar-Kandri Area, Maharashtra, Central India

Geological mapping and structural analysis of the manganese-bearing Sausar Group and associated rocks in Ramtek-Mansar-Kandri area, Maharashtra, have led to reinterpretation of stratigraphy and structure. A local stratigraphic succession for the Sausar supracrustal rocks, giving due weightage to lithologic critena and structural considerations, has been proposed which is different from the existing divergent lithostratigraphic successions suggested by different workers at different times. The lithologic unit interpreted as a conglomerate horizon by some earlier workers, near the contact of the granite gneiss and the Sausar Group in Mansar-Kandri area, has been reintmpreted to be of tectonic origin, Sausar Group preserves evidence of four generations of folding (F₁ to F₄). The map pattern is controlled by F₂ and F₄ whereas F₁ and F₃ have developed only on hand specimen to outcrop scale Ramtek synform, the major structural feature in the area, is a polyharmonic, second-generation fold with shallow southeasterly plunge and a steep to subvertical, WNW-ESE striking axial plane. It is not a large scale non-plane, non-cylindrical superposed fold (F₂ on F₁), as interpreted earlier. Regional metamorphism of pelitic-psammopelitic rocks possibly reached amphlbolite facies with peak metamorphic condition post-dating D₁ deformation.