Organic Matter (OM) Associated Uranium Mineralisation in Kaimur Group of Vindhyan Supergroup near Maha-Rampura, Gwalior District, Madhya Pradesh, India

Abstract

The Proterozoic Vindhyan Supergroup overlying Bundelkhand Granite Complex (BGC) presents an ideal environment for exploration of uranium mineralisation. Recent exploratory drilling in Kaimur Group of sandstone overlying unconformably the basement Bundelkhand granite at Maha Rampura area has revealed a significant correlatable uranium mineralisation. The mineralisation hosted by subfeldspathic arenite with reddish/ greenish shale intercalations enriched with organic matter is delineated. The subfeldspathic arenite has a definite marker bed with 1–2 m thickness located ∼ 30 m to 40 m above the unconformity. Organic matter (OM) is disseminated in subfeldspathic arenite and occurs within intergranular spaces as rounded globules. Uranium occurs within the subfeldspathic arenite as primary minerals i.e. uraninite and coffinite as well as in adsorbed form on organic matter and clay within the marker horizon. Significant correlatable uranium mineralisation with primary uranium minerals in Maha Rampura area thus opens up a broad exploration target in the entire Vindhyan Basin.