Stratigraphy of lower part of Amiran Formation in N.W and S.E of Khorramabad

Document Type : Original Research


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

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


In order to study of stratigraphy of Lower part of Amiran formation In Northwest and Southeast of Khorramabad, tow stratigraphic sections were chooses consist of Cham sangar section at Southeast and Tang-e shabikhon section at Northwest of Khorram Abad. In microbiostratigraphy investigations were identified 23 genuses and 35 various species of benthic foraminifera in these sections which are identified include:
Loftusia minor, L. harisoni, L. coxi, L. elongata, L. morgani, L. sp., Dicyclina shlumbergeri, D. sp., Minouxia lobata, M. sp., Cuneolina sp., Antalyna korayi, Psuedolithounella sp., Broekinella sp., Omphalocyclus macroporus, Orbitoides media, O. cancavatus, O. tissoti, O. apiculata, Siderolites calcitrapoides, S. sp., Rotalia trochidiformis, R. sp., Nezzazatinella sp., Vania anatolica, Valvulammina sp., Murciella sp., Trochospirsa sp., Idalina antiqe, Dictyoconella complanata, Cyclammina sp., Dictyoconus sp., Gavelinella sp., Goupillaudina sp., Miliolids.
According to the micropaleontology data, the age of Lower part of Amiran Formation at Northwest and Southeast of Khorramabad is middle to upper Maestrichtian. Micropaleontological data indicate that large quantity and size of agglutinate foraminifers in Lorestan area that seem Amiran formations flysh were effected to the agglutinate shell growing.