P P Chakraborty
Articles written in Journal of Earth System Science
Volume 111 Issue 4 December 2002 pp 379-390
Enriched13C/12C ratios with δ13C ∼3%0 (w.r.t PDB) of two Late Riphean (∼ 700-610 Ma) intracratonic carbonate successions viz., Bhander Limestone of Vindhyan Basin and Raipur Limestone of Chattisgarh Basin suggest higher organic productivity during this period. This view is supported by sedimentological evidence of higher biohermal growth and consequent increase in depositional relief in the low gradient ramp settings inferred for these basins. Oxygen isotope analysis of these carbonates show distinct segregation between enriched deeper water carbonate mudstone and depleted shallow water stromatolite facies that received fresh water influx. This shows that facies-specific analyses can be useful in understanding the depositional setting of these sediments.