Stratigraphy and Palaeontology
Hossein Gholamalian; Mohammad Kazem Kamali
Abstract
Pteriomorpha, Heterodonta, Paleoheterodonta and Anomalodesmata bivalves from the Kazhdumi Formation of the Geno and Gerash sections in the southeast of Zagros Mountains are studied here. In order to this research, bivalve speies are identified and described as follow: Arctica angulata, Birostrina ...
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Pteriomorpha, Heterodonta, Paleoheterodonta and Anomalodesmata bivalves from the Kazhdumi Formation of the Geno and Gerash sections in the southeast of Zagros Mountains are studied here. In order to this research, bivalve speies are identified and described as follow: Arctica angulata, Birostrina concentrica, Ceratostreon flabellatum, Crassatella manzourensis, Flaventia belviderensis, Granocardium productum, Gyrostrea delettrei, Illymatogyra africana, Mytiloides concentricus, Neithea dutrugei, Neithea sp. 1, Neithea sp. 2, Paraesa faba, Pinna cfcretacea, Pholadomya fabrina, Pholadomya vignesi, Protocardia hillana, Pterotrigonia scabra, Rhynchostreon suborbiculatum, Tenea delettrei, Venericardia deserti. Many of these species excluding Ceratostreon flabellatum, Illymatogyra africana, Neithea dutrugei and Pterotrigonia scabraare reported for the first time from Iran. Kazhdumi Formation disconformably overlies the top of the Dariyan Formation and underlies the Gurpi Formation.
Stratigraphy and Palaeontology
Hossein Gholamalian; Roya Fanati Rashidi
Abstract
Kazhdumi Formation strata in Anguran section (NW Bandar Abbas) are investigated and eight echinoid species belonging to eight genera have been identified. These species are: Tetragramma malbosii, Orthopsis ruppelli, Phyllobrissus aff. angustatus, Epiaster dartoni, Hemiaster sp., Pliotoxaster comanchei, ...
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Kazhdumi Formation strata in Anguran section (NW Bandar Abbas) are investigated and eight echinoid species belonging to eight genera have been identified. These species are: Tetragramma malbosii, Orthopsis ruppelli, Phyllobrissus aff. angustatus, Epiaster dartoni, Hemiaster sp., Pliotoxaster comanchei, Iraniaster douvillei, Coenholectypus planatus. Iraniaster douvillei that has already been reported from the Coniacian – Santonian beds of Lorestan Zone (West of Iran); is present in the Albian – Cenomanian strata of Anguran section. So; we can propose the new range of Middle Albian – Santonian for this species. Kazdumi Formation in the studied area has the age of Middle Albian to Early Cenomenian on the basis of foraminifers those accompany with echinoids. This formation conformably overlies the Dariyan Formation and disconfomably underlies the Gurpi Formation.
K. Kiarostami; S. H. Vaziri; B. Noori; S. Allahmadadi; F. Vakilbaghmisheh
Abstract
In order to investigate lithostratighraphical and biostratigraphical as well as determination of exact contact between the Sarvak and Ilam formations in oil well X-01 of Bahregansar field thin microscopic sections, final well reports and its illustrative diagram were studied. The Sarvak Formation with ...
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In order to investigate lithostratighraphical and biostratigraphical as well as determination of exact contact between the Sarvak and Ilam formations in oil well X-01 of Bahregansar field thin microscopic sections, final well reports and its illustrative diagram were studied. The Sarvak Formation with a thickness of 206 m overlies the black to dark-green marls of Kazhdomi Formation with a gradual contact. This formation can be divided into 2 members and consist mainly of dolomite and dolomitic limestone. The Ilam Formation is considered in a depth ranging from 2672 to 2678 m in the studied well based on studied section and is mainly formed of clay limestone and thin-bedded limestone. This formation is covered by Gurpi Formation with a gradual contact and has a disconformity contact with the Sarvak Formation. Moreover, the age of the Ilam Formation has been considered as Coniacian - Early Campanian which is formed of pelagic facies in the studied area. A number of 22 species belonging to 23 genera have been identified that 6 genera and 11 species belong to the Ilam Formation and 11 species of 17 genera belong to the Sarvak Formation. Considering the identified fauna in the Sarvak Formation, the three following biozones were identified conforming to biozones presented by Wind (1965):1-Nezzazata - Alveolinids Assemblage Zone # 25; 2-Rudist debris # 24; 3-"Oligostegina"facies # 26. Presented biozones and principle of super position indicate Cenomanian age for the Sarvak Formation that consist of pelagic and neretic facies. Moreover, the age of the Ilam Formation has been considered as Coniacian - Early Campanian which is formed of pelagic facies in the studied area.