TY - JOUR ID - 60516 TI - Lower Tithonian ammonites from the Chaman Bid Formation in northeastern Iran, Koppeh-Dagh Basin JO - Geopersia JA - GEOPE LA - en SN - 2228-7817 AU - Majidifard, Mahmoud Reza AU - Fuersich, Franz AU - Keupp, Helmut AU - Seyed Emami, Kazem AD - Research Institute for Earth Sciences, Geological Survey of Iran AD - GeoZentrum Nordbayern, Friedrich-August Universität Erlangen-Nürnberg AD - Freie Universität Berlin, Institut für Geologische Wissenschaften AD - School of Mining Engineering, University College of Engineering, University of Tehran Y1 - 2017 PY - 2017 VL - 7 IS - 1 SP - 11 EP - 26 KW - "Tithonian" KW - "ammonites" KW - "Chaman Bid Formation" KW - "Koppeh Dagh" DO - 10.22059/geope.2017.212475.648265 N2 - The type section of the Middle and Upper Jurassic Chaman Bid Formation is in the western Koppeh Dagh Basin (Northeast Iran). It is unusually thick and contains a rather rich ammonite fauna, ranging from Bathonian to Tithonian. The ammonites described here come from a 134-m-thick interval in the upper part of member (D) in the middle part of the formation, consisting of an alternation of grey limestone and marly limestone. The following ammonite families are present: Haploceratidae, Oppeliidae, Perisphinctidae, and Ataxioceratidae, among them the following taxa have being recorded for the first time from Iran: Phanerostephanus subsenex, Phanerostephanus aff. intermedius, Nothostephanus aff. kurdistanensis, Nannostephanus cf. subcomutus and Oxylenticeras cf. lepidum. This assemblage is belonging to the Lower Tithonian Semiforme Zone or even older zones. The Fallauxi Zone is represented by Richteria richteri. UR - https://geopersia.ut.ac.ir/article_60516.html L1 - https://geopersia.ut.ac.ir/article_60516_5ed577a15a1d0f5a460fff35d12f91c2.pdf ER -