عنوان مقاله [English]
نویسنده [English]چکیده [English]
Study of Aptian sediments in the Interior Fars Province confirm existence of shale beds interval in red color show pelagic facies and oxic environmental condition. Geochemical data (elemental and mineralogy analysis) release increasing in Fe and Mn and presence of Goethite in these sediments. Since that geochemical data confirm diagenesis condition in a close burial system, the red color of sediments can be attributed to iron bearing minerals that have been deposited in sedimentary basin. These sediment have been deposited in an oxidant condition which is completely different with previous organic rich sediments. The cause of the oxidant condition in deep oceanic environment is to reduce the temperature after the OAEs, which this change in water temperature has led to an increase in the oxidation potential of deep water basins, change in pattern of water circulation and eventually transfer of oxygen to these areas. Considering that the temperature reduction factor is the release of a large volume of carbon dioxide from the atmosphere in the form of organic-rich sediments, formation of these red oceanic layers during the Cretaceous is considered as an event subsequent to the anoxic event of the ocean.