Biostratigraphy and microfacies analysis of the Asmari Formation in SE of Aleshtar, Lorestan

The Asmari Formation in the Sarab-e Narm setion in south-east of Aleshtar town was measured and sampled in order to study its foraminiferal faunas and microfacies. Based on the stratigraphical distribution of the larger benthic foraminiferas in the studies section two assemblage zones have been recognized. Assemblage zone I represents a Aquitanian age and includes Miogypsina barsaensis, Peneroplis farsensis, Elphidium sp., Nummulitids sp. and Schlumbergina sp., Assemblage zone II is characteristic of Burdigalian age which consists of Borelis melo curdica, Meandropsina iranica, Austrotrillina cf. howchini, A. cf. striata, A. cf. asmariensis and Dendritina rangi. This section lacks lower Asmari Formation. According to the petrographic analysis of the deposits, five microfacies types were identified. The Asmari Formation has been deposited on a carbonate ramp in which facies belts of middle ramp and inner ramp are distinguishable.