57Fe Mössbauer spectroscopic study of organic-rich sediments (source rocks) from test wells CTP-1 and MDP-1 located in Eastern Krishna–Godavari basin, India

A large number of sub-surface sedimentary samples using Mössbauer spectroscopy were obtained from various depths of wells CTP-1 and MDP-1 drilled in Eastern Krishna–Godavari basin (KG basin) of India. Results indicate that iron is distributed in pyrite, siderite and in clay minerals, apart from these minerals an anomalously large presence of sulfate minerals was also found. Their presence indicates oxidizing conditions in sediments. Significance of presence of minerals, which show oxidizing conditions in context of source rock characterization, is discussed.