Radioactive Carbonaceous Material within the Fractured Bundelkhand Granite of Gwalior Basin at Dursendi, Gwalior District, Madhya Pradesh - A Petrographic Revelation

Radioactive carbonaceous matter, possibly of organic origin, with coffinite inclusions {U(SiO₄)_{1_x}(OH)_4x} are reported for the first time in the fractures within the core samples of highly deformed Bundelkhand granitoids in the Gwalior Basin. Intense hydrothermal alterations along these fractures are manifested in the form of silicification, argillic alteration (clay formation), chlontisation, ferruginisation and by sulphide formation. The globular radioactive carbonaceous matter is of organic origin and generally associated with silica rich veins. Globular nature of this carbonaceous matter indicates their formation from coagulation of smaller colloids in a low temperature hydrotherm. Mixing of descending oxidizing hydrotherm derived from basinal fluid rich in heavy metals, uranium, organic matter and ascending reducing fluid (hydrotherm) rich in H₂S and Si in these fracture zones has resulted in the precipitation of sulphides, secondary quartz, carbonaceous material and coffinite.