New Findings on the Dasycladacean Algae from the Fahliyan Formation in the Zagros Basin (SW of Iran)

Abstract

A very detailed biostratigraphical analysis, sequential interpretation and paleoecological investigations have been carried out based on the Dasycladacean algae and accompanied benthic foraminifera on the Fahliyan Formation in Kuh-e-Khartang and Kuh-e-Gavbast and correlated with Kuh-e-Surmeh, SW of Iran. Vertical variations of lithofacies and cyclic deposits in the shallow water carbonates can be interpreted in terms of sequence stratigraphy. Sequential interpretations reveal at least three 2nd-order and 3rd-order sequences with several parasequence sets throughout the studied successions. The sequences are given in Berrisian – Early Valanginian, Early Valanginian and Hauterivian age. Family Dasycladacea and subfamily Clypeineae are the most frequent and occasionally reported for the first time from the Zagros Basin and/or from the Southern Tethys. The paleoecological and paleobathymetrical investigations indicate that these strata have been deposited in a shallow internal subtidal (protected lagoon) to external subtidal and platform margins with the interval depths of 5 m to 40 m and their salinity ranges from normal marine to super saturated (hypersaline) conditions.