List of Articles Nannofossil

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  1 - Determining the deposits attributed to the Gurpi Formation based on the calcareous nannofossil located in SW Borojen, Chahar-Mahal and Bakhtiyari provinces
  Saeideh Senemari Fariba Foroughi
  Calcareous nannofossils are useful in determining the relative age of the Cretaceous strata. In this study, the Gurpi Formation with a thickness of 445 m at the Kuh-e Sabz syncline located in southwest of Borojen city is investigated based on the calcareous nannofossils More

  Calcareous nannofossils are useful in determining the relative age of the Cretaceous strata. In this study, the Gurpi Formation with a thickness of 445 m at the Kuh-e Sabz syncline located in southwest of Borojen city is investigated based on the calcareous nannofossils. As a result of this study, 20 genera and 37 species of calcareous nannofossil were identified. Based on distribution of these index calcareous nannofossils, seven bio-zones were recognized including: Calculites obscurus Zone (CC17/ late Santonian- early Campanian), Aspidolithus parcus Zone (CC18/ early Campanian), Calculites ovalis Zone (CC19/ late Early Campanian), Ceratolithoides aculeus Zone (CC20/ late Early Campanian), Quadrum sissinghii Zone (CC21/ early Late Campanian), Quadrum trifidum Zone (CC22/ late Late Campanian) and Tranolithus phacelosus Zone (CC23/ latest Campanian–early Maastrichtian), that corresponding to upper part of NC17 - NC20 and UC13-UC17. Based on the identified zones, the age of the studied intervals is Late Santonian/Early Campanian to latest Campanian/early Maastrichtian. The study of the Gurpi Formation in the Kuh-e Sabz syncline, shows that the sedimentation began at the Late Santonian/Early Campanian time and continued up to the latest Campanian/early Maastrichtian. Then, with a sudden drop in the depth of sedimentary basin, the Tarbur Formation gradually deposited on the top of the Gurpi Formation. Manuscript profile
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  2 - Calcareous nannofossil biostratigraphy in the upper part of the Garau Formation in the Sheikh Saleh section in Northwest of Kermanshah, Lurestan Province (Zagros Basin)
  سعیده  سنماری
  In this study, the upper part of the Garau Formation with a thickness of 24 m in the section of Sheikh Saleh anticline located in the northwest of Kermanshah was investigated from the calcareous nannofossils. In this section, the Garau Formation is mainly composed of me More

  In this study, the upper part of the Garau Formation with a thickness of 24 m in the section of Sheikh Saleh anticline located in the northwest of Kermanshah was investigated from the calcareous nannofossils. In this section, the Garau Formation is mainly composed of medium bedded argillaceous limestone. In order to introduce the index species and biozones, 17 slides from the Garau Formation were studied, which resulted in the identification of three biozones. As a result of this study, 20 species and 15 genera of calcareous nannofossils were identified. Based on the obtained biozones, the age of the upper part of the Garau Formation in the studied section is suggested the late early Cenomanian to the late late Cenomanian. This age is corresponding to the upper part of Eiffellithus turriseiffelii Zone (CC9), Microrhabdulus decorates Zone (CC10), lower part of Quadrum gartneri Zone (CC11) from the Sissingh (1977) zonation and UC1, UC2, UC3, and lower part of UC7 from the Burnett (1998) zonation. Manuscript profile
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  3 - Calcareous nannofossil biostratigraphy of the Cretaceous deposits in Khunik startigraphic section (West Qaen, eastern Iran)
  M. Notghi Moghaddam F. Jalili S. Senemari
  In this research, the biostratigraphy of the Cretaceous deposits was investigated in the eastern margin of Lut Block in Khunik startigraphic section, west of Qaen, based on calcareous nannofossils. The stratigraphic interval mainly consists of marls with sandstone inter More

  In this research, the biostratigraphy of the Cretaceous deposits was investigated in the eastern margin of Lut Block in Khunik startigraphic section, west of Qaen, based on calcareous nannofossils. The stratigraphic interval mainly consists of marls with sandstone interlayers (196 m thick). According to the systematic studies, 30 nannofossil species belonging to 20 genera were identified. Based on the presence of index calcareous nannofossils such as Calcicalathina oblongata, Speetonia colligata, Eiffellithus striatus and the fossil assemblages Calcicalathina oblongata Zone (CC3), Cretarhabdus loriei Zone (CC4) and Lithraphidites bollii Zone (CC5) these deposits are equivalent to NK3A subzone – middle part of NC5B subzone. According to the determined biozones, early Valanginian to late Hauterivian age was suggested for the studied interval. Manuscript profile
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  4 - Lithostratigraphy and biostratigraphy of the foram and diatome layers equivalent deposits based on calcareous nannofossils in the Gorgan Plain: A reference to evolution and paleogeography of the South Caspian Basin
  M. Sharafi N. Mousavi M. Moradpour B. Beiranvand A. Bayet-Goll F. Taati
  Paleocene-Miocene sediments in the central part of the Gorgan Plain were studied to evaluate lithostratigraphy, biostratigraphy and reconstruction of the paleogeography of the South Caspian Basin (SCB). Based on nannofossils distribution in the studied interval, the fol More

  Paleocene-Miocene sediments in the central part of the Gorgan Plain were studied to evaluate lithostratigraphy, biostratigraphy and reconstruction of the paleogeography of the South Caspian Basin (SCB). Based on nannofossils distribution in the studied interval, the following points were identified: Foram layers equivalent sediments have Thanetian –Eocene age and Upper Maykop- Diatom equivalent sediments have Middle-Late Miocene age. Evaluation of the nannofossils distribution in the studied interval has clarified a major unconformity between lower Paleocene-Eocene sediments and the upper Middle-late Miocene sediments. This unconformity is coincident with collisional event of the Afro-Arabia and Eurasia Plates and rising of the surrounding mountain ranges around the Caspian Basin including Alborz and Kopet-Dagh Mountains. Nannofossils distribution of the studied succession displays that the SCB was connected to the Black Sea and Mediterranean Basin in the lower Middle Miocene and was isolated in the Middle-Late Miocene. The interpreted east-west running seismic lines displays a clear increase in the sediment thickness and accommodation space from eastern to western part of the Gorgan Plain. The higher available accommodation space from east to west of the Gorgan Plain led to a delay in the subaerial exposure in the western part of the Gorgan Plain due to rising of the Kopet-Dagh and Alborz Ranges. This interpretation is consistent with the lack of the Paleocene-Eocene sediments and presence of the Cretaceous sediments below the major unconformity in the eastern part of the Gorgan Plain and presence of the Paleocene-Eocene sediment below the unconformity in the studied area. Manuscript profile