M Nouredini; M Yazdi; A Ashouri; S Rahmati
Abstract
The Lower Carboniferous deposits (Shishtu II Formation) is exposed in the Banarizeh section, Southeastern Isfahan, Central Iran. The Shishtu II Formation is characterized by continental to shallow marine deposits, where it unconformably overlies the Alluvial deposits and is unconformably overlain by ...
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The Lower Carboniferous deposits (Shishtu II Formation) is exposed in the Banarizeh section, Southeastern Isfahan, Central Iran. The Shishtu II Formation is characterized by continental to shallow marine deposits, where it unconformably overlies the Alluvial deposits and is unconformably overlain by the Sardar Formation. The thickness of Shishtu II Formation reach to 195m and contain moderate diversity, high richness Holothurian sclerites assemblages and other skeletal particles of scatter Crinoids, Brachiopods and Corals. The systematic studies and taxonomic investigation carried out on the collected samples from studies area led to recognition of 8 species belonging mainly to 4 families (Calclamnidae, Achistridae, Palaeocaudinidae, Theelidae). The Holothurian sclerites in Shishtu II Formation are dominantly as: Eocaudina subhexagona, Eocaudina ovalis, Microantyx permiana, Mercedescaudina langeri, Protocaudina hexagonaria, Achistrum monochordata, Thalattocanthus Consonus. Based on sratigraphical distribution of the Holothurian sclerites, Tournaisian- Visean age is suggested for Shishtu II Formation.
M Mannani; M Yazdi
Abstract
The Nayband Formation in North of Isfahan includesfive Members: 1- Gelkan Member (marl and sandstone), 2- Bidestan Member (sandstone and reefal limestone), 3- Howz- e- Sheikh Member (marl and sandstone), 4- Howz- e- Khan Member (marl and reefal Limestone) and 5- Qadir Member (marl and sandstone). The ...
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The Nayband Formation in North of Isfahan includesfive Members: 1- Gelkan Member (marl and sandstone), 2- Bidestan Member (sandstone and reefal limestone), 3- Howz- e- Sheikh Member (marl and sandstone), 4- Howz- e- Khan Member (marl and reefal Limestone) and 5- Qadir Member (marl and sandstone). The biostromal limestones of Bidestan and Howz-e- Khan Members represent a typical known key bed in North of Isfahan. In Bidestan and Howz-e- Khan Members (Nayband Formation), coral reefs grow up and their distribution are significant in the biostromal limestone of Bidestan and Howz-e- Khan Members of Nayband Formation.Twelve genera and 31 species of Scleractinian corals were recognized in the sereefal members. They included: Reimani phylliidae, Margarophylliidae, Coryphylliidae, Cyclophyllidae, Astraeomorphidae, Pamiroseriidae, Stylophyllidae and Actinastraeidae families. According to the field observations and evidences, laboratory studies and analysis, measurements of the coral size and the destroyed epitecha of the corals, it could beguessed that Scleractinian corals survive below the storm wave base (about 20 meters depth) but they tolerated many storms. Morphology of Scleractinian corals of Late Triassic sea (North of Isfahan) indicates in adequate living conditions and high energy environment. Corals have major role in reconstruction of Paleoenviroment of the Late Triassic units of the North of Isfahan (Nayband Formation) in Dizlu section.