first record of fresh water gastropods and sedimentary facies of nezam-abad area, south-east bam, iran

sediments of the nezam-abad area, south-east of bam have been studied for the first time. sedimentary facies are composed of thin-bedded clay, silt and fine grained sand interbedded with thin laminated limestone. chemical analysis of x-ray florescent indicates that more than 50% of sediments consist of silisium and aluminum oxide that can be used for reconstruction of environment. ninety eight gastropod specimens were collected and two genera and one species of discus sp., goniobasis sp. and hydrobia neglecta were introduced for the first time. occurrence of lithofacies together with gastropod faunas and also absence of evaporate indicate a fresh water lake environment during pleistocene to recent time.