S Abbasi; B Hamdi; M.R Majidifard
Abstract
Sampling and study of Devonian deposits in North West Iran has done in two separate sections. 1) Illangareh section, 20 km far from NE the Maku city 2) peyr-es-hag composite section, situated South Jufa (W of Peyr-es-hag and Chay kasan villages). Because less work has been undertaken in the cited sections, ...
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Sampling and study of Devonian deposits in North West Iran has done in two separate sections. 1) Illangareh section, 20 km far from NE the Maku city 2) peyr-es-hag composite section, situated South Jufa (W of Peyr-es-hag and Chay kasan villages). Because less work has been undertaken in the cited sections, in this research, microremains (fish teeth, scales and bone fragments) of Cartilaginous fish (Chondrichtyes), Osteichtyes (Acanthodians), fauna are known from the Devonian deposits. Index microvertebrates obtained from the cited above sections are: Siberiodus mirabilis, Phoebodus gothicus, Phoebodus turnerae, , Body scale Holonema sp., Sarcopterygian scale, Ischnacanthid jaw, Cheiracanthus sp., Ertychius intermedius Cladodus wildungensis. According to biostratigraphy and paleogeography these microremains can be comparing with other parts of Iran, neighbors, other parts of world. This assemblage show spread of shallow shelf environment of the northern margin of Gondwana during Middle-Late Devonian time.
M. mohamadi; M. Yazdi
Abstract
There are many precious microremains of chondrichtyans (cartilage fishes) in calcareous beds of Geirud Formation. These micro remains consist of teeth, branchial denticles and sales species and genus of the family and subfamily: Phoebodontidae, Protacrodontoidea, HybodontoideaandCtenacanthoidea. Geirud ...
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There are many precious microremains of chondrichtyans (cartilage fishes) in calcareous beds of Geirud Formation. These micro remains consist of teeth, branchial denticles and sales species and genus of the family and subfamily: Phoebodontidae, Protacrodontoidea, HybodontoideaandCtenacanthoidea. Geirud Formation consists of alternating silisiclastics and calcareous beds with 1-2 basaltic units well distributed in Central Alborz. The upper Devonian/Lower carboniferous age assigned to Geirud Formation. The name of the Formation has been driven from type locality – Geirud village in north of Tehran. The upper Devonian/Lower carboniferous deposits have been studied along Alborz Mountain range and Central Iran. Faunal similarity between Famennian deposits of Central Iran and Eastern Alborz with Geirud Formation (Hairapetian & Klug 2002) confirm the basin relationship between these areas, also faunal relationship between these fauna and the fauna of Famennian in Morocco and Algeria confirm that these deposits belong to shelves of North Gondwanaland (Ginter & al., 2002). These fauna are associated with conodonts of expansa zone.