List of articles (by subject) stratigraphy
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Open Access Article
1 - Biostratigraphy of the deposits of the Katkoyeh Formation in the Gezoiye section, northwest of Kerman (southeast of Zarand) based on conodont fauna.
Farzad Poursalehi Ali Bahrami Hamed Ameri Gustavo Gabriel VoldmanThe Ordovician marine sedimentary sequences of Iran are located in different structural blocks along the northern margin of Gondwana. In the north of the Kerman Basin, Ordovician sedimentary sequences named Katkoyeh Formation have been introduced, which consist of 70 to MoreThe Ordovician marine sedimentary sequences of Iran are located in different structural blocks along the northern margin of Gondwana. In the north of the Kerman Basin, Ordovician sedimentary sequences named Katkoyeh Formation have been introduced, which consist of 70 to 300 meters of siliceous siliceous rocks, one or two thin carbonate horizons in the upper part, and pyroclastic deposits. Traditionally, the Cambrian-Ordovician boundary in the Kerman Basin has been determined between the Hatken Dolomite Member of the Kuhbanan Formation (Late Furongian) and the Lower Shale Member of the Katkuye Formation. However, determining the location of the previous Tremadocine boundary is uncertain because no fossils have been documented from this interval. For the purpose of biostratigraphy of the Katkuye formation in Kerman basin, Gezoye section with an approximate thickness of about 170 meters was selected. In this section, the Katkoyeh Formation is located on the Hatken Dolomite Member and under the Shabjareh Formation sandstones of Silurian age. In the Gezoiye section, due to the action of basalt dikes and intense tectonics in the region, the limestone layers containing fossils have been severely altered, and during three sampling stages, 320 conodonts were recovered from the carbonate horizon of the upper part of this formation, and 3 Genus and 7 species were identified and based on this, three conodont ranges were recorded: 1) Icriodella superba Range Zone (Katian - ? Hirnantian; Late Ordovician), 2) Amorphognathus ordovicicus Range Zone (Katian - Late Ordovician), 3) Amorphognathus superbus Range Zone (Katian - ? Hirnantian; Late Ordovician). Late Ordovician age in the Katkuye formation in the Gezoye section with at least three species of the conodont genus Icriodella (I. superba, I. deflecta, (I. cf. discrete and two species of A. superbus) Amorphognathus, A. ordovicicus) determined and led to the identification of the Katian-?Hirnantian rocks. Manuscript profile -
Open Access Article
2 - Lithostratigraphy and Biostratigraphy of Pabdeh Formation based on planktonic foraminifera in the Ilam dam section (south Ilam_ Zagros sedimentari basin)
somaye taherizade Mohammad Vahidinia Mohammadhossein mahmoudi gharaiiZagros Sedimentary basin is located in the south and southwest of Iran and Pabdeh Formation is one of the most important Cenozoic units of Zagros Sedimentary basin. In addition, Pabdeh Formation is of special importance as one of the source rocks of Zagros Sedimentary b MoreZagros Sedimentary basin is located in the south and southwest of Iran and Pabdeh Formation is one of the most important Cenozoic units of Zagros Sedimentary basin. In addition, Pabdeh Formation is of special importance as one of the source rocks of Zagros Sedimentary basin. In order to study the Lithostratigraphic and Biostratigraphic rocks of Pabdeh Formation, the section of Ilam dam in the northwest of Zagros sedimentary basin has been selected and sampled. 360 samples were taken, of which 260 washing samples and 100 thin section samples were prepared. Based on the studies performed on these samples, 25 genera and 105 species have been identified in the Ilam dam section. 26 biozones and 2 sub-biozones have been identified based on the biological zoning of Wade et al., 2011 in the Tethys area. Based on the identified biozones, the age of Pabdeh Formation in the Ilam dam section, Middle Danian-Early Aquitanian has been obtained. The deposits of Pabdeh Formation in the section of Ilam dam have a thickness of 764 m (beginning of Pabdeh to the beginning of Kalhor anhydrite) which includes purple shale units (2 Units), marl limestone with lower limestone, cherti limestone, marl limestone with upper limestone. The lower boundary of Pabdeh Formation in this section is conform and continuous with shales and marls of Gurpi Formation but its upper boundary with the gypsums of the Asmari formation is most likely accompanied by a disconform. Manuscript profile