Microfacies and sequence stratigraphy of the Qom Formation; Goylar section; Southwest of Zanjan province

Document Type : Original Article

Author

Assistant Professor, Department of Geology, Faculty of Science, Payame Noor University (PNU), Saveh, Iran

Abstract

Introduction
Sedimentary environment and sequence stratigraphic studies of the Qom Formation as a reservoir rock is of utmost importance in terms of the potential for hydrocarbon resources. Bozorgnia (1966) divided the Qom Formation into nine members (a, b, c1, c2, c3, c4, d, e, f) in the age of Rupelian to Burdigalian, which the National Stratigraphic Committee of Iran accepted. This research is focused on paleoenvironmental interpretations and sequence stratigraphy of the Qom Formation in the Goylar stratigraphic section, which is located northwest of the structural zone of Central Iran.
Materials and Methods
A total of 64 thin sections of hard samples of Qom Formation in the Goylar section have been prepared. Due to the similarity of foraminifera in the Qom and Asmari formations, the biozonation of the Asmari Formation, which is documented by Wynd (1965), Adams & Bourgeois (1967), and Laursen et al. (2009), has been used in this research. Determination of planktonic foraminifera has been done only by studying thin sections. To recognition of the facies and sedimentary model of the Qom Formation, studies of Reed (1995) and Flugel (2010) have been used, and to undertake sequence stratigraphy, the model of Hunt & Tucker (1993, 1995) is used.
Discussion and Conclusion
Qom Formation in the Goylar section is 155 meters in thickness. Qom Formation includes thick-bedded limestone, thin to medium bedded sandstone, shale and marl, reef-coral limestone, and green marl and argillaceous limestone alternation. According to the lithological characteristics, Qom Formation in this area can be equivalent to member f. A total of 24 genera and 18 species, including 17 genera and species of Benthic foraminifera: Borelis melocurdica, Psuedoilthonella richelli, Peneroplis evolutus, Peneroplis thomasi, Heterolopa dutemplei, Asterigerina rotula, Valvulina sp.1, Valvulina sp.2, Pyrgo sp.1., Amphistegina spp., Spiroloculina sp., Quinqueloculina sp., Austrotrillina sp., Miogypsina sp., Lenticulina sp., Elphidium sp.1., Rotalia sp., Nodosaria sp., Textularia sp.; and 7 genera and 13 species of planktonic foraminifera with an axial incision in thin sections including Globigerinoides primordius, Globigerinoides subquadratus, Globigerinoides triloba, Globigerinoides immaturus, Paragloborotalia mayeri, Paragloborotalia spp., Globigerina praebulloides, Globigerina sp., Globigerinella obesa, Globorotalia archeomenardii, Globorotalia sp., Praeorbulina transitoria, Bolivina sp.
According to paleontological studies and based on the stratigraphic distribution of foraminifera, Borelis melocurdica-Borelis melo melo Assemblage Zone (Burdigalian, Early Miocene) has been recognized certainty for the Qom Formation. Facies analysis, including variety in fauna features, facies geometry, and sedimentary textures, has produced seven microfacies related to the four facies belts of the lagoon, reef, slope, and open marine. Deep Shelf/Slope Facies Belt: Mf.1. Planktonic foraminifera wackestone-packstone, Mf.2. Bioclast Miogypsina packstone, and Mf.3. Amphistegina coral corallinacea packstone; Shoal/ Reef deposits facies Belt: Mf.4. Coral Boundstone, and Mf.5. Bioclast bryozoan corallinacea Packstone, and Lagoonal facies Belt: Mf.6. Bioclast Packstone, and Mf.7. Porcelaneous foraminifera Packstone.
Consequently, of lacking the sediment gravity flows, turbidity facies, and presence of the reef facies deposits (25 percent of the Qom deposits (including coral boundstone, algae, and bryozoan, sedimentation of the Qom formation occurred likely on an open shelf. Facies distribution chart demonstrates that the beginning and closure of the Qom Formation sedimentation occurred significantly in the continental slope environment (without considering the possible erosion phenomenon). Based on sequence stratigraphic studies, five depositional sequences and six-sequence surfaces have been separated (the first and sixth sequence surfaces being of the type-1). Comparing the sequence levels of this study with the sequences identified in other regions of the Central Iran Basin and the European Basin shows a good correlation.
References
Adams, T.D., & Bourgeois, F., 1967. Asmari biostratigraphy. Iranian Oil Operating Companies. Geological and Exploration Division, Report 1074: 1-37. (Unpublished)
Bozorgnia, F., 1966. Qom Formation stratigraphy of the Central Basin of Iran and its intercontinental position. Bulletin of the Iranian Petroleum Institute, 24: 69-75.
Flügel, E., 2010. Microfacies of Carbonate Rocks, Analysis Interpretation and Application. Springer-Verlage, Berline, Heidelberg. 984 p.
Hunt, D., & Tucker, M.E., 1992. Stranded parasequences and the forced regressive wedge systems tract: deposition during base-level fall. Sedimentary Geology, 81: 1-9.
Hunt, D., & Tucker, M.E., 1993. Sequence stratigraphy of carbonate shelves with an example from the mid-Cretaceous (Urgonian) of southeast France. International Association of Sedimentologists, Special Publication, 18: 307–341.
Laursen, G.V, Monibi, S., Allan, T.L., Pickard, N.A.H., Hosseiney, A., Vincent, B., Hamon, Y., Van Buchem, F.S.H., Moallemi, A., & Driullion, G., 2009. The Asmari Formation revisited: Changed stratigraphic allocation and new biozonation. First international petroleum conference & exhibition, Shiraz, Iran, 1-5.
Mohammadi, E., Vaziri, M.R., & Dastanpour, M., 2015. Biostratigraphy of the nummulitids and Lepidocyclinids bearing Qom Formation based on larger benthic foraminifera (Sanandaj–Sirjan forearc basin and Central Iran back-arc basin, Iran). Arabian Journal of Geosciences, 8 (1): 403-423.
Read, J.F., 1995. Overview of carbonate platform sequences, cycle stratigraphy, and reservoirs in greenhouse and icehouse worlds. SEPM, Short Course Notes, 35:1-102
Wynd, J.G., 1965. Biofacies of the Iranian Oil Consortium Agreement area. Iranian Oil Operating Companies, Geological and Exploration Division, Report 1082. (Unpublished).

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آقانباتی،ع.، 1383. زمین شناسی ایران. سازمان زمین‌شناسی و اکتشافات معدنی کشور، 586 ص.
اسدی مهماندوستی، ا.، دانشیان، ج.، مارگیر، ن.، 1398. ریزرخساره‌ها، محیط‌ رسوبى و فرآیندهاى دیاژنزی سازند قم در برش چینه شناسی خانی‌آباد، جنوب خاوری کاشان. رخساره‌های رسوبی، 12 (1): 1-22.
دانشیان، ج.، اسدی، ا.، و درخشانی، ل.، 1396. ریزرخساره، محیط رسوبی و چینه نگاری سکانسی سازند قم در برش ده نمک، شمال شرق گرمسار. فصلنامه زمین شناسی ایران، 11 : 23-43.
جلالی، م.، صادقی، ع.، آدابی، م، ح.، 1396. ریزرخساره‌ها، محیط رسوبی و چینه نگاری سکانسی سازند قم در چاه یورته شاه1 و برش سطحی موره‌کوه (جنوب تهران). پژوهش‌های چینه نگاری و رسوب شناسی، 66 (1): 25-48.
لطفی، م. 1380 . نقشه زمین شناسی ماه نشان، مقیاس 1:100000. سازمان زمین شناسی و اکتشافات معدنی کشور.
Abaie, I., Ansari, H.J., Badakhshan, A., & Jaafari, A., 1964. History and development of the Alborz and Sarajeh fields of Central Iran. Bulletin of Iranian Petroleum Institute, 15: 561-574.
Adams, T.D., & Bourgeois, F., 1967. Asmari biostratigraphy. Iranian Oil Operating Companies. Geological and Exploration Division, Report 1074: 1-37. (Unpublished)
Amirshahkarami, M., & Karavan, M., 2015. Microfacies models and sequence stratigraphic architecture of the OligoceneeMiocene Qom Formation, south of Qom City, Iran. Geoscience Frontiers, 6: 593-604.
Bolli, H.M., & Saunders, J.B., 1985. Oligocene to Holocene low latitude planktonic foraminifera. In: Bolli, H.M., Saunders, J.B., Perch-Nielson, K., (eds.), Plankton stratigraphy. Cambridge University Press, 155–262.
Bozorgnia, F., 1966. Qom Formation stratigraphy of the Central Basin of Iran and its intercontinental position. Bulletin of the Iranian Petroleum Institute, 24: 69-75.
Flügel, E., 2010. Microfacies of Carbonate Rocks, Analysis Interpretation and Application. Springer-Verlage, Berline, Heidelberg. 984 p.
Furrer, M.A., & Soder, P.A., 1955. The Oligo-Miocene Formation in the Qom region (Iran).
Processing of 4th World Petroleum Congress, 6-15 June, Roma, Italy, 267-277.
Hardenbol, J., Thierry, J., Farley, M.B., Jacquin, T., De Graclansky, P.C., & Vail, P.R., 1998. Mesozoic and Cenozoic sequence chronostratigraphic framework of European basins. SEPM Special Publications, 60: 3-14.
Hunt, D., & Tucker, M.E., 1992. Stranded parasequences and the forced regressive wedge systems tract: deposition during base level fall. Sedimentary Geology, 81: 1-9.
Hunt, D., & Tucker, M.E., 1993. Sequence stratigraphy of carbonate shelves with an example from the mid-Cretaceous (Urgonian) of southeast France. International Association of Sedimentologists, Special Publication, 18: 307–341.
Iaccarino, S., Premoli-Silva, I., Biolzi, M., Foresi, L.M., Lirer, F., & Petrizzo, M.R., 2005. Practical Manual of Oligocene to Middle Miocene Planktonic Foraminifera. International School on Planktonic Foraminifera, course IV, 124 p.
Kennett, J.M., & Srinivasan, M.S., 1983. Neogene planktonic foraminifera, a phylogenetic atlas. Hutchinson Ross publish Company Pensylvania, 1-263.
Laursen, G.V, Monibi, S., Allan, T.L., Pickard, N.A.H., Hosseiney, A., Vincent, B., Hamon, Y., Van Buchem, F.S.H., Moallemi, A., & Driullion, G., 2009. The Asmari Formation revisited: Changed stratigraphic allocation and new biozonation. First international petroleum conference & exhibition, Shiraz, Iran, 1-5.
Loeblich, A.R.Jr., & Tappan, E., 1988. Forminiferal genera & their classification. Van Nostrand Reinhold Campany, New York, 1-970.
Loftus, W.K., 1855. On the geology of the Turko-Persian Frontier and of the districts adjoining, Quart. Journal of Geological Society of London, 11: 247-344.
Mohammadi, E., 2020. Sedimentary facies and depositional environments of the Oligocene–early Miocene marine Qom Formation, Central Iran Back‑Arc Basin, Iran (northeastern margin of the Tethyan Seaway). Carbonate and Evaporites, 35:20, https://doi.org/10.1007/s13146-020-00553-0
Mohammadi, E., Hasanzadeh-Dastgerdi, M., Safari, A., & Vaziri-Moghaddam, H., 2019. Microfacies and depositional environments of the Qom Formation in Barzok area, SW Kashan Iran. Carbonate and Evaporites, 34: 1293–1306.
Mohammadi, E., Safari, A., Vaziri-Moghadam, H., Vaziri, M. R., & Ghaedi, M., 2011. Microfacies analysis and paleoenviornmental interpretation of the Qom Formation, South of the Kashan, Central Iran. Carbonates Evaporites, 26: 255–271.
Mohammadi, E., Vaziri, M.R., & Dastanpour, M., 2015. Biostratigraphy of the nummulitids and lepidocyclinids bearing Qom Formation based on larger benthic foraminifera (Sanandaj–Sirjan fore arc basin and Central Iran back-arc basin, Iran). Arabian Journal of Geosciences, 8 (1): 403-423.
Nebelsick, J.H., Rasser, M., & Bassi, D., 2005. Facies dynamic in Eocene to Oligocene Circumalpine carbonates. Facies, 51 (4): 197-216.
Read, J.F., 1995. Overview of carbonate platform sequences, cycle stratigraphy and reservoirs in greenhouse and icehouse worlds. SEPM, Short Course Notes, 35:1-102
Reuter, M., Piller, W.E., Harzhauser, M., Mandic, O., Berning, B., Rögl, F., Kroh, A., Aubry, M.P., Wielandt-Schuster, U., & Hamedani, A., 2009. The Oligo-Miocene Qom Formation (Iran): evidence for an Early Burdigalian restriction of the Tethyan Seaway and closure of its Iranian gateways. International Journal of Earth Sciences, 98 (3): 627-650.
Seddighi, M., Vaziri-Moghaddam, H., Taheri, A., & Ghabeishavi, A., 2011. Depositional environment and constraining factors on the facies architecture of the Qom Formation, Central Basin, Iran. Historical Biology, 24: 91-100.
Stocklin, J., & Setudehina, A., 1991. Stratigraphic lexicon of Iran. Geological Survey of Iran. 18: 1–376.
Vaziri-Moghaddam, H., & Torabi, H., 2004. Biofacies and sequance strayigraphy of the Oligocene succession, Central basin, Iran. Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, Stuttgart, 6: 321-344.
Wade, B. S., Pearson, P. N., Berggren, W. A., & Pälike, H., 2011. Review and revision of Cenozoic tropical planktonic foraminiferal biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale. Earth Science Review, 104 (1-3): 111-142.
Wilson, J.L., 1975. Carbonate facies in geologic history. 1st edition, Springer-Verlag, New York, 1-471.
Wynd, J.G., 1965. Biofacies of the Iranian Oil Consortium Agreement area. Iranian Oil Operating Companies, Geological and Exploration Division, Report 1082. (Unpublished).
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