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.
M. Mohammadi; A. Ernst; M. Yazdi
Abstract
Two bryozoan species are described from the Geirud Formation (Upper Devonian) of Central Alborz. The Geirud Formation is a sequence of nearly 340 meters of alternating silisiclastics and limestone and 1-2 andesitic lava units, with extensive exposures in the Central Alborz mountains. ...
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Two bryozoan species are described from the Geirud Formation (Upper Devonian) of Central Alborz. The Geirud Formation is a sequence of nearly 340 meters of alternating silisiclastics and limestone and 1-2 andesitic lava units, with extensive exposures in the Central Alborz mountains. The study comprises the Type Section of the Geirud Formation in the Geirud valley and two sections in Zaigun and Lalun valleys near the Type Section, all in northern Tehran (Fig.1). In some calcareous beds we found bryozoan species from Famennian. Trepostome Schulgina mutabilis Troizkaya, 1975 is known from the Upper Devonian (Famennian) of Central Kazakhstan. The Ascopora .sp. is the earliest known representative of habdomesine genus Ascopora Trautschold, 1876. This is the first study on the bryozoans of the Geirud Formation in Central Alborz.
M. Yazdi; H. R. Pakzad; M. Mashkour; R. Elhami; M. Javeri; F. Biglari
Abstract
Determining and studying collected lithic assemblages, biota remains and deposited beds (regarding to sedimentology) of two rock shelters in the age of Late Pleistocene to recent interval in central Iran were the aims of this research. Mobarekeh (Qaleh Bozi) and Yekeh Chah (near Golpayegan) are two sites ...
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Determining and studying collected lithic assemblages, biota remains and deposited beds (regarding to sedimentology) of two rock shelters in the age of Late Pleistocene to recent interval in central Iran were the aims of this research. Mobarekeh (Qaleh Bozi) and Yekeh Chah (near Golpayegan) are two sites in which remains of consumed and hunted biota by human were checked by this research. Lithic assemblages are studied considering their sources. Mousterian lithic assemblages from Qaleh Bozi caves and rock shelters (HassanAbadCaves) are made of silica pebbles (limestone with Nummulite or cherty beds in the age of Paleocene to Eocene time interval) that hominids had collected from the Zayandeh Rud River in the Middle Paleolithic Period. Finally it should be stated that lithic artifacts in Yekeh Chah are mostly Quartzite sandy shale (probably belong to Jurassic). Black beds (charcoal lenses) in Qaleh Bozi and Yekeh Chah caves were sampled and washed for Determining biota remains and sedimentary components. All washed samples from two localities had remains of: burned wood (charcoal), large vertebrate mammals (mostly horse), vertebrate and micro vertebrates (fish, rodent, reptile and amphibian), egg of birds, seeds and grass. SEM photos related to hunted and consumed birds’ beak and nails from Mobarekeh and Yekeh Chah confirmed that the food of man in those localities could be similar. This research is first report the presence of hunter-gatherer hominids in Central Iran (Mousterian). Lithic assemblages are collected from Separab Naein in the age of Mesolithic and from Tapeh Ashena (Chadegan) in the age of Neolithic as well.
S. M. Hosseini-Nezhad; M. Yazdi; M. Ghobadi-Pour; H. Gholamalian
Abstract
Geirud formation deposits of Kalariz in the Eastern Alborz start with a relatively thick sequence of sandstone, shale, and red, white and brown colored siltstone changing into yellow dolomitic layers, fossiliferous limestone and shaly or marly limestone. This formation ...
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Geirud formation deposits of Kalariz in the Eastern Alborz start with a relatively thick sequence of sandstone, shale, and red, white and brown colored siltstone changing into yellow dolomitic layers, fossiliferous limestone and shaly or marly limestone. This formation lies over Mila formation with a disconformity and covered transitionally by limestones of Mobarak formation. In the above mentioned sequence, numerous and various conodonts and brachiopods were identified. Based on the distribution of brachiopoda, two assemblage zones and based on the conodonts, four assemblage zones were recognized with Famennian and Strunian age. The first brachiopoda biozone, equivalent to the first and second conodont biozones, belongs to early Famennian age (older than late crepida zone and romboidea to late trachytera zone) and the second Brachiopoda biozone which is equivalent to conodont biozone of number three and four has the late Famennian age (postera to late expansa zone and praesulcata zone). Paleontological and stratigraphical evidence indicates that Frasnian sediments are absent in the study area.
