Depositional and diagenetic impact on reservoir quality of the Asmari carbonate reservoir, Naft-Sefid Oilfield, SW Iran

Document Type : Research Paper


Department of Geology, Science and Research Branch, Islamic Azad University, Tehran, Iran


The Oligo-Miocene Asmari Formation with main carbonate and evaporate lithology is the most prolific reservoir in the Dezful Embayment, south-west of Iran. Depositional and diagenetic effects on reservoir quality in the sequence stratigraphic framework were carried out on the basis of petrographic investigation, petrophysical logs, and core measurement porosity and permeability data. Petrographic analysis resulted in the identification of 12 microfacies classified in 5 sub-environments including tidal flat, lagoon, barrier, shallow open marine and basin, which indicate deposition in a homoclinal ramp setting. Tidal flat, lagoonal and barrier microfacies are mostly present in the upper and middle parts of the Asmari Formation, while outer ramp microfacies largely developed in the middle part. Anhydrite/calcite cementation, compaction, dolomitization, dissolution, and fracturing are the main diagenetic controlling factors on petrophysical properties. Fracturing, dolomitization, and dissolution are contributed to reservoir quality enhancement, while compaction and cementation had negative effects on reservoir quality. The main controlling factor on their reservoir quality was depositional characteristics and/or a facies-dependent diagenesis. The studied successions are represented by 3 third-order sequences of early Aquitanian, late Aquitanian and early Burdigalian age that largely deposited in the highstand systems tract (HST) stage. The Burdigalian sequence represent best reservoir quality due to further dolomitization and dissolution especially close to the sequence boundary.


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Adams, A. E., Mackenzie, W. S., 1998. A Colour Atlas of Carbonate Sediments and Rocks Under the Microscope. Manson Publishing Ltd, London.##
Aghanabati, A., 2004. Geology of Iran. Geological survey of Iran, p.582.##
Ahr, W.M., 2008. Geology of carbonate reservoirs. John Wiley and Sons, Chichester, p.296.##
Al-Aasm, I. S., Veizer, J., 1986. Diagenetic stabilization of aragonite and low-Mg calcite; I, Trace elements in rudists. Journal of Sedimentary Research, 56 (1): 138-152.##
Alavi, M., 2004. Regional stratigraphy of the Zagros fold-thrust belt of Iran and its pro foreland
evolution. American journal of science. 304 (1): 1-20.##
Alsharhan, A.S. and Kendall, C.G.S.C., 1986. Precambrian to Jurassic rocks of Arabian Gulf and
adjacent areas: their facies, depositional setting, and hydrocarbon habitat. American Association of Petroleum Geologists Bulletin, 70(8): 977-1002.##
Alsharhan, A.S. and Whittle, G.L., 1995. Carbonate-evaporite sequences of the Late Jurassic, southern and southwestern Arabian Gulf. American Association of Petroleum Geologists Bulletin, 79 (11): 1608-1630.##
Aqrawi, A. 2007. The Control of fracturing and dolomitisation on 3D reservoir property distribution of the Asmari Formation (Oligocene-Lower Miocene), Dezful Embayment, SW Iran. International Petroleum Technology Conference held in Dubai, U.A.E., 4-6 December, 7 p.##
Aqrawi, A.A.M., Keramati, M., Ehrenberg, S.N., Pickard, N., Moallemi, A., Svånå, T., Darke, G.,
Dickson, J.A.D., Oxtoby, N.H., 2006. The origin of dolomite in the Asmari formation (Oligocenelower Miocene), Dezful embayment, SW Iran. Journal of Petroleum Geology, 29 (4): 381-402.##
Avarjani, S., Mahboubi, A., Moussavi-Harami, R., Amiri-Bakhtiar, H., Brenner, R.L., 2015. Facies, depositional sequences, and biostratigraphy of the Oligo-Miocene Asmari Formation in Marun oilfield, North Dezful Embayment, Zagros Basin, SW Iran. Palaeoworld, 24 (3): 336-358.##
Bathurst, R. G. 1987. Diagenetically enhanced bedding in argillaceous platform limestones: stratified cementation and selective compaction. Sedimentology, 34 (5): 749-778.##
Berberian, M. and King, G.C.P., 1981. Towards a paleogeography and tectonic evolution of
Iran. Canadian Journal of Earth Sciences, 18 (2): 210-265.##
Burchette, T.P. and Wright, V.P., 1992. Carbonate ramp depositional systems. Sedimentary Geology, 79(1-4): 3-57.##
Buxton, M.W.N., Pedley, M., 1989. Short paper: a standardized model for Tethyan Tertiary carbonate ramps. Journal of the Geological Society, 146: 746-748.##
Chafetz, H.S., Imerito-Tetzlaff, A.A., Zhang, J.L., 1999. Stable isotope and elemental trends in
Pleistocene sabkha dolomites: Descending meteoric water vs. sulfate reduction. Journal of
Sedimentary Research, 69(1): 256-266.##
Daraei, M., Bayet-Goll, A. and Ansari, M., 2017. An integrated reservoir zonation in sequence
stratigraphic framework: A case from the Dezful Embayment, Zagros, Iran. Journal of
Petroleum Science and Engineering, 154: 389-404.##
Dickson, J.A.D., 1965. A modified staining technique for carbonates in thin section. Nature, 205(4971): 587.##
Duggan, J.P., Mountjoy, E.W. and Stasiuk, L.D., 2001. Fault-controlled dolomitization at Swan Hills Simonette oilfield (Devonian), deep basin west-central Alberta, Canada. Sedimentology, 48: 301-323.##
Dunham, R. J., 1962. Classification of carbonate rocks according to depositional texture. In: Ham, W.E., ed., Classification of Carbonate rocks: American Association of Petroleum Geologists Special Publications, 1: 108-121.##
Ehrenberg, S. N., N. A. H. Pickard, G. V. Laursen, S. Monibi, Z. K. Mossadegh, T. A.Sva˜na, A. A. M. Aqrawi, J. M. McArthur, M. F. Thirlwall, 2007. Strontium isotope stratigraphy of the Asmari
242 Haghighat et al. Formation (Oligocene- Lower Miocene), SW Iran, Journal of petroleum geology, 30: 107-128.##
Esteban, M., Taberner, C., 2003. Secondary porosity development during late burial in carbonate reservoirs as a result of mixing and/or cooling of brines. Journal of Geochemical Exploration, 78-79: 355-359.##
Farshi, M., Moussavi-Harami, R., Mahboubi, A., Khanehbad, M. and Golafshani, T., 2019. Reservoir rock typing using integrating geological and petrophysical properties for the Asmari Formation in the Gachsaran oil field, Zagros basin. Journal of Petroleum Science and Engineering, 176: 161-171.##
Flügel, E., 2004. Microfacies of carbonate rocks. Springer-Verlag, Berlin, Pp.976.##
Folk, R.L., 1965. Some aspects of recrystallization in ancient limestones. In: Pray LC, Murray RC (eds) Dolomitization and limestone diagenesis. American Association of Petroleum Geologists Special Publication, 13: 14-48.##
Hollis, C., Sharp, I., 2011. Albiane Cenomaniane Turonian carbonate-siliciclastic systems of the
Arabian Plate: advances in diagenesis, structure and reservoir modelling: introduction. Petroleum Geoscience, 17: 223-241.##
Husain, S. A., & Krouse, H. R. 1978. Sulphur isotope effects during the reaction of sulphate with
hydrogen sulphide. In Stable isotopes in the earth sciences. James, G. A., J. G. Wynd, 1965. Stratigraphic nomenclature of Iranian oil consortium agreement area, American Association of Petroleum Geologists Bulletin, 49: 2182-2245.##
Longman, M. W., 1980. Carbonates diagensis tetures from near surface diagenetic environment, Association of Petroleum Geologists Bulletin, 64(4): 461-487.##
Lucia, F.J., 2007. Carbonate Reservoir Characterization. Springer-Verlag, Berlin, p.341.##
Machel, H.G., 1999. Effects of groundwater flow on mineral diagenesis, with emphasis on carbonate aquifers: Hydrogeology Journal, 7: 94-107.##
Machel, H.G., 2005. Investigations of burial diagenesis in carbonate hydrocarbon reservoir rocks. Geoscience Canada.##
Melim, L. A., & Scholle, P. A. 2002. Dolomitization of the Capitan Formation forereef facies (Permian, west Texas and New Mexico): seepage reflux revisited. Sedimentology, 49(6): 1207-1227.##
Meyer, F.O., 2005. Anhydrite classification according to structure. Available from:
Moore, C.H., 2001. Carbonate reservoirs porosity evolution and diagenesis in a sequence stratigraphic framework: Amsterdam, Elsevier, 444 pp.##
Moradi, M., Moussavi-Harami, R., Mahboubi, A., Khanehbad, M. and Ghabeishavi, A., 2017. Rock typing using geological and petrophysical data in the Asmari reservoir, Aghajari Oilfield, SW Iran. Journal of Petroleum Science and Engineering, 152: 523-537.##
Mossadegh, Z.K., Haig, D.W., Allan, T., Adabi, M.H. and Sadeghi, A., 2009. Salinity changes during late Oligocene to early Miocene Asmari formation deposition, Zagros Mountains, Iran.
Palaeogeography, Palaeoclimatology, Palaeoecology, 272(1-2): 17-36.##
Motiei, H., 1993. Stratigraphy of the Zagros, Treatise on the geology of Iran,Ministry of Mines and Metals, Geological Survey of Iran, Tehran.##
Saller, A. H., Henderson, N. 1998. Distribution of porosity and permeability in platform dolomites: Insight from the Permian of west Texas. Association of Petroleum Geologist bulletin, 82 (8): 1528- 1550.##
Sampo, M. 1969. In: Cuvillier, J. and S churmann, H. M. E. (eds) Microfacies and Microfossils of the Zagros Area Southwestern Iran (From Pre Permian to Miocene). International Sedimentary
Petrographical Series. E. J. Brill, Leiden, 12: 1-102.##
Scholle, P. A., Halley, R. B. 1985. Burial diagenesis: out of sight, out of mind!
Scholle, P. A., Ulmer-Scholle, D. S. 2003. A Color Guide to the Petrography of Carbonate Rocks:
Grains, Textures, Porosity, Diagenesis, American Association of Petroleum Geologists, 77.##
Sepehr, M. and Cosgrove, J.W., 2004. Structural framework of the Zagros fold-thrust belt, Iran. Marine and Petroleum Geology, 21(7): 829-843.##
Seyrafian, A. and Hamedani, A. 2003. Microfacies and paleoenvironmental interpretation of the lower Asmari Formation (Oligocene), north-central Zagros Basin, Iran. Neues Jahrbuch für Geologie und Paläontologie-Monatshefte, 3: 164-174.##
Sherkati, S. and Letouzey, J., 2004. Variation of structural style and basin evolution in the central Zagros (Izeh zone and Dezful Embayment), Iran. Marine and Petroleum Geology, 21 (5): 535-554. Geopersia 2021, 11(1): 219-243 243##
Tucker, M. E., 2001. Sedimentary Petrology: An Introduction to the Origin of Sedimentary Rocks, Wiley.##
Tucker, M. Wright, V. P. 1990. Carbonate sediments and limestones: constituents. Carbonate
sedimentology. Blackwell, Oxford, 1-27.##
Tucker, M.E., 1994. Sedimentary petrology: an introduction to the origin of sedimentary rocks.
Blackwell Scientific Publication, 260 pp.##
Vail, P.R., 1991. The stratigraphic signatures of tectonics, eustacy and sedimentology-an overview. Cycles and events in stratigraphy. 617-659.##
Van Buchem, F.S.P., Allan, T.L., Laursen, G.V., Lotfpour, M., Moallemi, A., Monibi, S., Motiei, H.,
Pickard, N.A.H., Tahmasbi, A.R., Vedrenne, V. and Vincent, B., 2010. Regional stratigraphic
architecture and reservoir types of the Oligo-Miocene deposits in the Dezful Embayment (Asmari and Pabdeh Formations) SW Iran. Geological Society Special Publications, 329 (1): 219-263.##
Van Wagoner, J.C., Mitchum, R.M., Campion, K.M. and Rahmanian, V.D., 1990. Siliciclastic sequencem stratigraphy in well logs, cores, and outcrops: concepts for high-resolution correlation of time and facies, Association of Petroleum Geologists Methods Exploration. Series. 7: 55p.##
Vaziri-Moghaddam, H., Kimiagari, M., Taheri, A., 2006. Depositional environment and sequence
stratigraphy of the Oligo-Miocene Asmari Formation in SW Iran. Facies, 52: 41-51.##
Warren, J, 2000. Dolomite: Occurrence, evolution and economically important association: Earth
Science Review, 52: 1-18##
Warren, J, 2000. Evaporites Sediments Resources and Hydrocarbons, Springer Verlag, Berlin, Pp.1053.##
Wilson, J. L., 1975. Carbonate facies in geological history: New York, Springer. Pp.471.##