The study of microfacies and sedimentary environments of the Kazhdumi Formation northeast of Shiraz

Document Type : Original Research


1 Department of Geology, Islamic Azad University - Shiraz Branch, Shiraz, Iran

2 Department of geology, Faculty of Science, Islamic Azad University - North Tehran Branch, Tehran, Iran

3 Department of Geology, Faculty of Basic Sciences, Sciences & Research Branch, Islamic Azad University, Tehran, Iran


The Kazhdumi Formation northeast of Shiraz (Gadvan Mount) is composed of 247.7 meters of carbonate rocks. Its lower contact is disconformable with the Dariyan Formation, which is marked by iron oxide. Its upper contact with the Sarvak Formation is gradual. After sampling, 80 thin sections have been provided. Based on index microfossils, Albian-Early Cenomanian age has been determined for Kazhdumi Formation and 12 carbonate microfacies have been recognized, each of which has been deposited in different parts of lagoon and open marine sedimentary environments. Facies analysis of the Kazhdumi Formation in the study area and comparison with modern sedimentary environments indicate that these facies have been deposited in a ramp type of carbonate platform. The vertical changes of microfacies suggest 6 sedimentary cycles on the scale of several ten meters. However, each of these cycles contains several smaller cycles, each of several-meter scale.