Original paper
Macrocephalitinae (Ammonoidea, Middle Jurassic) from North and Central Iran
Seyed-Emami, Kazem; Raoufian, Ahmad; Mönnig, Eckhard
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen Band 278 Heft 3 (2015), p. 257 - 279
published: Dec 1, 2015
ArtNo. ESP155027803001, Price: 29.00 €
Abstract
Macrocephalites is one of the most common and cosmopolitan ammonites of the Middle Jurassic and partially an important guide fossil in Europe and the Indo-East-African Province. The ammonites of this genus inhabited the shelf seas around the edges of the Tehtys Ocean from the Late Bathonian to the earliest Middle Callovian. In Iran Macrocephalites is rather rare, we only know a dozen of localities in the North Iran (Alborz and Binalud mountains) and Central Iran. Most of the specimens come from the locality named Talu near Dāmghān in the eastern Alborz, from the marls and limestones of the Dalichai Formation. The Macrocephalites fauna of Talu seem to belong to the middle part of the Bullatus Zone (Lower Callovian). Further collections from localities in Binalud, Koppeh Dagh and Tabas areas indicate horizons of other ages. Thus, a sequence of 8 ammonite assemblages can be proposed for the Upper Bathonian and Lower Callovian of Iran. In Iran Macrocephalites is only frequent in the Bullatus Zone, but also occurs in the Prahecquense Subzone. Only a single Macrocephalites was found in the Gracilis Zone at Kelariz. The Macrocephalites gracilis fauna, which is typical of the middle Gracilis Zone, and the M. opis-semilaevis fauna from the Lower-Middle Callovian boundary seems to be absent in Iran. Overall the Middle Jurassic ammonite fauna of North and Central Iran belongs to the Submediterranean Province.
Keywords
macrocephalites • iran • ammonoidea • middle jurassic • biostratigraphy