Calcareous nannofossils from chalky limestone intervals of the Abderaz formation in the Kopet Dagh range, NE Iran

محورهای موضوعی : Mineralogy

Somayeh Sanjary ¹ , Fatemeh Hadavi ² , Marziyeh Notghi Moghaddam ³ , Mohsen Allameh ⁴

1 - Department of Geology, Ferdowsi University of Mashhad, International Campus, Iran
2 - Department of Geology, Ferdowsi University of Mashhad, Iran
3 - Department of Geology, Payame Noor University, Tehran, Iran
4 - Department of Geology, Mashhad Branch, Islamic Azad University, Mashhad, Iran

تاریخ دریافت : 1397/08/26 تاریخ پذیرش : 1397/08/26 تاریخ انتشار : 1397/10/11

کلید واژه: Iran, Calcareous nannofossil, Chalky limestone, Abderaz, Kopet Dagh,

چکیده مقاله :

A biostratigraphic study based on calcareous nannofossils was performed on the chalky limestone from the Abderaz Formation in the Mozduran section (Kopet Dagh basin, NE Iran). Semiquantitative estimates of total nannofossil and single species abundances showed that calcareous nannofossil assemblages are common and their preservation is good. In this study 37 species have been identified in chalky limestone beds. The following biohorizons were identified: the first occurrence (FO) of Broinsonia parca parca; the last occurrence (LO) of Marthasterites furcatus; the FO of Ceratolithoides aculeus; and the FO of Uniplanarius sissinghii. Based on nannofossil assemblages' four biozones were determined in this section which is the time equivalent of UC14 to UC15cTP of (Burnett 1998), and CC18 to CC21 of (Roth et al. 1986). According to present biozones, early Campanian to early late Campanian ages are suggested. Calcareous nannofossils allow the detailed reconstruction of paleoecological trends in the chalky limestone beds. The chalky limestone of the Abderaz Formation was deposited in a shallow-marine environment, at relatively low latitude with low primary productivity.

چکیده انگلیسی:

A biostratigraphic study based on calcareous nannofossils was performed on the chalky limestone from the Abderaz Formation in the Mozduran section (Kopet Dagh basin, NE Iran). Semiquantitative estimates of total nannofossil and single species abundances showed that calcareous nannofossil assemblages are common and their preservation is good. In this study 37 species have been identified in chalky limestone beds. The following biohorizons were identified: the first occurrence (FO) of Broinsonia parca parca; the last occurrence (LO) of Marthasterites furcatus; the FO of Ceratolithoides aculeus; and the FO of Uniplanarius sissinghii. Based on nannofossil assemblages' four biozones were determined in this section which is the time equivalent of UC14 to UC15cTP of (Burnett 1998), and CC18 to CC21 of (Roth et al. 1986). According to present biozones, early Campanian to early late Campanian ages are suggested. Calcareous nannofossils allow the detailed reconstruction of paleoecological trends in the chalky limestone beds. The chalky limestone of the Abderaz Formation was deposited in a shallow-marine environment, at relatively low latitude with low primary productivity.

منابع و مأخذ:

1. Afshar-Harb A (1969) A brief history of geological exploration and geology of the Sarakhs area and the Khangiran gas field, Bulletin of the Iranian petroleum Institute 37: 86-96.


2. Afshar-Harb A (1979) The stratigraphy, tectonics and petroleum geology of the Kopet Dagh region, northern Iran, Unpub1.PhD thesis, University of London.


3. Alavi M, Vaziri H, Seyed Emami K, Lasemi Y (1997) The Triassic and associated rocks of the Aghdarintervals are as Incentral and northeastern Iran as remnant of the southe rn Tura nian active continental margin, GSA Bulletin 109:1563 – 1575.


4. Al-badrani, OA, Mahmood RM (2014) Study of Nannoliths from Upper Cretaceous Shiranish Formation, Higran area, Northern Iraq, Arabian Journal of Geosciences 12: 5571-5578.


5.  


6.  


7.  


8. Bukry D (1973) Coccolith and silicoflagellate stratigraphy, Tasman Sea and southwestern Pacific Ocean, Deep Sea Drilling Project Leg 21, Initial Reports of the Deep Sea Drilling Project 21:885–893.


9. Burnett JA (1998) Upper Cretaceous. In: Bown, P. R. (Ed.), Calcareous Nannofossil Biostratigraphy, Chapman and Hall, Cambridge :132–199.


10. Buryakovsky LA, Chilinger GV, Aminzadeh F (2001) Petroleum geology of the South Caspian Basin, Gulf Professional Publishing USA 442.


11. Erba E (2006) The first 150 million years history of calcareous nannoplankton: Biosphere –geosphere interactions, Palaeo Journal 232: 237- 250


12. Erba E, Castradori D, Guasti G, Ripepe M (1992) Calcareous nannofossils and Milankovitch cycles: the example of the Albian Gault Clay Formation (southern England), Palaeogeogr Palaeoclimatol Palaeoecol 93: 47- 69.


13. Florindo F, Siegert M (2009) Geophysical Union, Antarctic Research Series 56, Washington: 31–60.


14. Hadavi F, Notghi Moghaddam M (2002) Calcareous nannofossils from the Chalky Limestone in the Kopet- Dagh range, NE Iran, Journal oJ Nannoplankton Research 24: 110.


15. Hamza, KH, Esam Z (2014) Calcareous Nannofossil Biostratingraphy and Stage Boundaries of the Santonian-Eocene Successions in Wadi El Mizeira Northeastern Sina, International Journal of Geosciences 5: 432-449.


16. Herrle J, Pross J, Friedrich O, Kobler P, Hemleben C (2003) Forcing mechanisms for mid-Cretaceous black shale formation: evidence from the Upper Aptian and Lower Albian of the Vocontian Basin (SE France), Palaeo Journal 190: 399- 426.


17. Huber BT (1998) Perspective: tropical paradise at the Cretaceous poles, Science 282:2199–2200.


18. Huber BT, Watkins DK (1992) Biogeography of Campanian–Maastrichtian calcareous plankton in the region of the Southern Ocean: Paleogeographic and Paleoclimatic implications. In: Kennett JP, Warnke DA. (Eds.), The Antarctic Paleoenvironment, A Perspective on Global Change. American.


19. Kaya-Ozer C (2014) Calcareous Nannofossil assemblage changes and stable isotope data from Maastrichtian to Selandian in the Akveren Formation Western Black Sea, Arabian Journal of Geosciences 3: 1233-1247.


20. Moussavi-Harami R (2009) Facies analysis and depositional sequences of the Upper Jurassic Mozduran Formation, a carbonate reservoir in the Kopet Dagh, Journal of Petroleum Geology 32(3):235-260.


21. Perch-Nielsen K (1985) Mesozoic Calcareous Nannofossils , In: Bolli H. M., Saunders, J. B., Perch-Nielsen  K (Eds.). Plankton Stratigraphy, Cambridge University: 329-426.


22. Roth PH, Krumbach KR (1986) Middle Cretaceous calcareous nannofossil biogeography and preservation in the Atlantic and Indian oceans, implications for paleoceanography, Mar Micropaleontol 10: 235- 266


23. Sissingh W (1977) Biostratigraphy of Cretaceous calcareous nannoplankton, Geologie en Mijnbouw 56: 37-65.


24. Tavakoli E, Ashuri AR, Vahidiniya M (2007) Microstratigraphy and sedimentary environment of Abderaz Formation in Ghalehzu and Zangelanlu sections,  Proceeding of 11th Symposium of geological society of Iran.  Mashhad 613.


25. Thierstein HR (1976) Mesozoic calcareous nannoplankton biostratigraphy of marine sediments, Mar Micropaleontol 1: 325- 362


26. Ulmishek G (2004) Petroleum geology and resources of the Amo-Darya Basin, Turkmenistan, Uzbekistan, Afghanistan, and Iran, US geological survey Bulletin 2201-4, 32.


27. Watkins DK (1992) Upper Cretaceous nannofossils from Leg 120, Kerguelen, Southern Ocean, Proc. ODP. Scientific Research 120: 343- 370.


28. Watkins DK (1996) Upper Cretaceous calcareous nannofossil biostratigraphy and paleoecology of the Southern Oceon. ln Alicia Moguilesvky and Robin Whatley (eds.), Microfossils and Oceanic Environments, Universityof Wales Aberystwyth- Press 355-381.


29. Williams JR, Bralower TJ (1995) Nannofossil assemblages, fine fraction stable isotopes, and the paleoceanography of the Valanginian-Barremian (Early Cretaceous), North Sea Basin, Paleoceanography 10: 815- 839.