Document Type : Original Research Paper


Department of Geology, Payame Noor Universtiy, Tehran, Iran


The Asmari carbonate formation in Lorestan is seen in the form of a medium to the thick limestone-rich layer of benthic foraminifera and often as a rock formation. In this study, the stratigraphic sequence of Asmari carbonate formation in the Chenareh Anticline section located in the south of Lorestan basin and Amiran Anticline section located in the middle part of Lorestan basin were studied in terms of lithology and micro biostratigraphy. The thickness of the Chenareh Section was 180 meters and the Section of Amiran Anticline was 158 meters. In total, more than 290 thin sections of both were prepared and examined in the laboratory. The results of fossil studies based on the expansion of foraminifera finally lead to the introduction and presentation of 1 Assemblage biozone in the Amiran anticline section and 3 Assemblage biozones related to the Chenareh anticline stratigraphic section. Accordingly, the age of the Asmari Formation is in the Chenareh section is Oligo-Miocene (Chattian-Bordigalian) and in the Amiran section is Miocene (Bordigalin). According to the lithostratigraphic studies, the border of the Asmari Formation in both sections of Chenareh and Amiran with Shabazan Formation is progressive-continuous and discontinuous, and in both sections of the upper boundary with Gachsaran Formation can be seen in the same way as evaporative sediments.


Main Subjects

Adabi, M. H., Kakemem, U., and Sadeghi, A., 2016. Sedimentary facies, depositional environment,and sequence stratigraphy of Oligocene–Miocene shallow water carbonate from the Rig Mountain, Zagros basin (SW Iran). Carbonates and evaporites, 31(1), 69-85. 
Adams, T. D. & Bourgeois, F., 1967- Asmari biostratigraphy. Geological and Exploration Iranian, Offshore Oil Company Report, No. 1074.
Alavi, M., 2004. Regional stratigraphy of the Zagros fold-thrust belt of Iran and its Proforland evolution. American Journal of Sciences V.304, p.1-20.
Bahroudi,  A.,  and  Koyi,  H.  A.,  2003. Effect  of  spatial  distribution  of Hormuz salt on deformation style in the Zagros fold and thrust belt: ananalogue modelling approach. Journal of Geological Society of London, V.160, p.1–15.
Busk, H.G., and Mayo, H.T., 1918. Some Notes on the Geology of the Persian Oil Fields. Institution of Petroleum Technologists,  V.5, p.5-26.
Ehrenberg, S. N., Pickard, N. A., Laursen, G.V., Monibi, S., Mossadegh, Z.K., Svånå, T.A., Aqrawi, A., Mc Arthur, J.M., and Thirlwall, M. F., 2007. Strontium isotope stratigraphy of the Asmari Formation (Oligocene–Lower Miocene), Sw Iran. Journal of Petroleum Geology. V.107, p.128. 
Heydari, E., Hassanzadeh, J., Wade, W. J., and Ghazi, A. M., 2003. Permian-Triassic boundary interval in the Abadeh section of  Iran with implications for mass extinction, Part 1: Palaeogeography, Palaeoclimatology, Palaeoecology Journal, V.193, p.405-423.
Homke, S., 2007. Timing of Shortening and Uplift of  the Pusht-E Kuh arc in the Zagros Fold-and- Thrust belt IRAN. A Combiend Magnetostratigraphy and Apatite Thermochronology Analysis, Universidad de Barcelona Facultad de Geología, Departamento de G eodinámica y Geofísica.
Homke, S., Vergés, J., Serra-Kiel, J., Bernaola, G., Sharp, I., Garcés, M., Montero-Verdú, I., Karpuz, R.,  and Goodarzi, M. H., 2009. Late Cretaceous–Paleocene formation of the proto-Zagros foreland basin, Lurestan Province, SW Iran. Geological Society of  America Bulletin V.121, p.963–978. 10.1130/B26035.1.
James, G.A., and Wynd, J.C., 1965. Stratigraphic nomenclature of Iranian oil consortium    agreement area: American Association of Petroleum Geologists Bulletin, V.49(2), p.94-156.
Laursen, G., Monibi, S., Allan, T., Pickard, N., Hosseiney, A., Vincent, B., Hamon, Y., Van Buchem, V., Moallemi, A., and Druillion, G., 2009. The Asmari Formation revisited: changed stratigraphic allocation and new biozonation. Shiraz 2009-1st EAGE International Petroleum Conference and Exhibition, European Association of Geoscientists & Engineers.
Lees, G.M., 1933. Reservior Rocks of Persian oil fields. American Association of Petroleum Bulletin, V.17, p.229-240. DOI:10.1306/3D932B32-16B1-11D7-8645000102C1865D.
Nikfard, M., Vaziri Moghaddam, H., Seyrafian, A., Behdad, A., and Shabafrooz, R.,  2020.  A review of the Oligo–Miocene larger benthic foraminifera in the Zagros basin, Iran; New insights into biozonation and palaeogeographical maps, Revue de Micropaléontologie, V. 66, 100408.
Pattinson, R., and Takin, M., 1971. Geological significance of Dezful embay-ment boundaries, IOOC, report No.1166 (Unpublished report) 10.1144/0016-764902-110.
Pirouz, M., Simpson, G., and Chiaradia, M., 2015. Constraint on foreland basin migra-tion in the Zagros mountain belt using Sr isotope stratigraphy. Basin Research Journal, V.27,  p.714-728.
Richardson, R. K., 1924. The Geology and Oil Measures of South West Persia. Institution of Petroleum Technologists, V.43, p.256 – 283.
Reichel, M., 1937. Etude sur les alveolines, Mem. Soc. Paleont Suisse, V.57/4, p.1-93. 
Sadeghi, R., Vaziri-Moghaddam, M., and Taheri, A., 2011. Microfacies and sedimentary environment of the Oligocene sequence (Asmari Formation) in Fars sub-basin, Zagros Mountains southwest Iran, Facies Carbonate Sedimentology and Paleoecology Journal, V.57(3), p.431-446.
Saleh, Z., and Seyrafian, A., 2013. Facies and depositional sequences of the Asmari Formation, Shajabil anticline, North of the Izeh Zone, Zagros Basin, Iran. Acta Geologica Sinica (English Edition),  V.87(6): p.1520–1532.
Sepehr, M., Cosgrove, J., and Moieni, M., 2006. The impact of cover rock rheology on the style of folding in the Zagros fold-thrust belt. Basin Research Journal, V.427(1-4): p.265-281. DOI: 10.1016/j.tecto.2006.05.021.
Serra-Kiel, J., Hottinger, L., Caus, E., Drobne, K., Ferrandez, C., Jauhri, A.K., Less, G., Pavlovec, R., Pignatti, J., Samso, J.M., Schaub, H., Sirel, E., Strougo, A., Tambareau, Y., Tosequella, J., and Zakrevskaya, E., 1998. Larger foraminiferal biostratigraphy of the Tethyan Paleocene and Eocene. Bulletin de la Socie´te´ Ge´ologique de France. V.169: p.281-299. 
Seyrafian, A., Vaziri-Moghaddam, H., Arzani, N., and Taheri, A., 2011. Facies analysis of the Asmari Formation in central and north-central Zagros basin, southwest Iran: Biostratigraphy, paleoecology and diagenesis. Revista Mexicana de Ciencias Geológicas, V.28( 3): p.439-458.
Taheri, M. R., Vaziri-Moghaddam, H., Taheri, A., and Ghabeishavi, A., 2017.  Biostratigraphy and paleoecology of the oligo-miocene Asmari formation in the Izeh zone (Zagros Basin, SW Iran). Boletín de la Sociedad Geológica Mexicana, V.69 (1): p.59–85.
Talbot, C.J., and Alavi, M., 1996. The Past of a Future Syntaxis across the Zagros. In: Alsop, G.I., Blundell, D.J. and Davison, I., Ed., Salt Tectonics, V. 100, Geological Society, London, P.89-109.
Thomas, N., 1948. The Asmari Limestone of Southwest Iran. National Iranian Oil Company, Report 706. unpublished.
Van Buchem, F.S., Allan, T.L., Laursen, G.V., Lotfpour, M., Moallemi, A., Monibi, S., Motiei, H., Pickard, N.A., Tahmasbi, A.R., Vedrenne, V., and Vincent, B., 2010. Regional stratigraphic architecture and reservoir types of the Oligo-Miocene de-posits in the Dezful Embayment (Asmari and Pabdeh Formations) SW Iran. Geol. Soc. (Lond.) Spec. Publ. V.329, p.219–263.
Vaziri-Moghaddam, H., Kimiagari, M., and Taheri, A., 2006. Depositional environment and sequence stratigraphy of the Oligo-Miocene Asmari Formation in SW Iran.  V.52(1): p.41-51.
Vaziri-Moghaddam, H., Seyrafian, A., Taheri, A., and Motiei, H., 2010. Oligocene-Miocene ramp system (Asmari Formation) in the NW of the Zagros basin, Iran: Microfacies, paleoenvironment and depositional sequence. Revista Mexicana de Ciencias Geológicas, 27: 56-71.
Wynd, J. G., 1965. Biofacies of the Iranian consortium- agreement area, Report 1082,  Tehran, Iranian Oil Operating Companies, Geological and Exploration Division, unpublished. 
Zoeram, F. Z., Vahidinia, M., Sadeghi, A., Mahboubi, A., and Bakhtiar, H. A., 2015. Larger benthic foraminifera: a tool for biostratigraphy. facies analysis and paleoenvironmental interpretations of the Oligo-Miocene carbonates. NW Central Zagros Basin, Iran. Arabian Journal of Geosciences. V.8(2): p.931-949.