Impact of Microfacies, Sedimentary Environment, and Diagenesis on the Reservoir Quality of Ilam Formation in Yadman Field

Document Type : Original Research Article

Authors

Department of Sedimentary Basin and Petroleum, Faculty of Earth Science, Shahid Beheshti University, Tehran, Iran

Abstract

To investigate the microfossils, microfacies, depositional environment, and diagenetic processes with in the Ilam Formation in Abadan Plain, Well Yadman-1 was studied. This research involved the study of 440 microscopic thin sections obtained from both core and cutting samples. The classification of carbonate rocks followed Dunham's method, microfacies were identified using Fluegel and Wilson's approach, and porosity was defined based on Choquette and Perry's classification. The microfacies analysis unveiled the existence of 10 distinct microfacies, which could be classified into 4 microfacies belts corresponding to shoal, mid-ramp, outer ramp, and basin environments. Notably, the studied facies exhibited a gradual transition and were devoid of reef facies, turbidite deposits, reworked carbonates, slumped and slid facies, oncoides, cortoids, and aggregate grains. These characteristics indicate the deposition of the Ilam Formation on a carbonate ramp of the single slope (homocline) type. Furthermore, various diagenetic processes were identified within the Ilam Formation, including dissolution, cementation, dolomitization, stylolite, pyritization, compaction, and fracturing. Based on the identified microfossils in the framework of two biozones with Santonian ages, zones 30 and 26 Wynd, the age of the Ilam Formation has been determined.

Keywords

Main Subjects

References

Aghanabati, A., 2003. Geology of Iran. Geological and Mining Organization Publications.
Ahr, W.M., 2008. Summary: Geology of carbonate reservoirs. In: Geology of carbonate reservoirs, pp. 200–254.
Asadi Mehmandosti, E., Abdolmaleki, S., Ghalavand, H., et al., 2023. Variation of geochemical data and sedimentary characteristics in the Upper Cretaceous Ilam Formation, a case study from southwest Iran. Palaeobiodiversity and Palaeoenvironments, 103, 71–93.
Asadi Mehmandosti, E., Daneshian, J. & Mohammad Panah, M. F., 2020. Depositional-diagenetic and geochemical characteristics of the Ilam Formation in northwest of Abdanan, Kabir Kuh. Journal of Stratigraphy and Sedimentology Researches, 35(4), 77–104.
Basso, M., Belila, A.M.P., Chinelatto, G.F., Souza, J.P., DA, P. & Vidal, A.C., 2020. Sedimentology and petrophysical analysis of pre‑salt lacustrine carbonate reservoir from the Santos Basin, southeast Brazil.
Burchette, T.P. & Wright, V.P., 1992. Carbonate ramp depositional systems. Sedimentary Geology, 79(1), 3–57.
Choquette, P.W. & Pray, L.C., 1970. Geologic nomenclature and classification of porosity in sedimentary carbonates. AAPG Bulletin, 54, 207–250.
Dunham, R.J., 1962. Classification of carbonate rocks according to depositional texture. In: Ham, W. E. (Ed.), Classification of carbonate rocks-A symposium, Vol. 1, p. 0. American Association of Petroleum Geologists.
Falcon, N.L., 1974. Southern Iran: Zagros Mountains. In: Geological Society Special Publication, 4, 199–211.
Flugel, E., 2010. Type of cementation, 2nd ed., pp. 294–295.
Gholizadeh, M., Adabia, M., Sadeghi, A., Ghasemi, M. & Moradi, M., 2022. Sedimentary environment, diagenesis, sequence stratigraphy, and reservoir quality of the Ilam Formation in Dezful Embayment and Abadan Plain in South-West Iran.
Ghoreyshi, S.S., Mehrabi, H. & Tavakoli, V., 2024. Reservoir characterization of the Ilam Formation using the integrated core data and petrophysical logs in an oilfield in the Abadan Plain, SW Iran. Journal of Petroleum Research, 34(1403–5), 129–158.
Hassani Givo, M., 2003. The impact of pore geometry on the reservoir quality of the Ilam and Sarvak formations in wells 1 and 3 of the Azadegan Field. University of Tehran.
Irani Kourabbaslou, B., Mousavi Harami, R., Mahboobi, A. & Kordkhodaei, A., 2015. Diagenetic processes and their impact on reservoir quality of the Asmari Formation in the Kopal Oil Field. Scientific and Research Quarterly, 9(18).
James, G.A. & Wynd, J.G., 1965. Stratigraphic nomenclature of Iranian Oil Consortium Agreement Area. AAPG Bulletin, 49(12), 2182–2245.
Khodaei, N., Rezaee, P., Honarmand, J., et al., 2021. Controls of depositional facies and diagenetic processes on reservoir quality of the Santonian carbonate sequences (Ilam Formation) in the Abadan Plain, Iran. Carbonates and Evaporites, 36, 19.
Khatir, R., Jahani, D., Aleali, M. & Ghadimvand, N.K., 2019. Facies, sedimentary environment, diagenesis and sequence stratigraphy of the Ilam Formation in the Darquain oil field, southwest of Iran. Environment and Ecology, 37(4B), 1612–1626.
Lucia, F.J., 2007. Carbonate reservoir characterization.
Mehrabi, H., Bagherpour, B. & Honarmand, J., 2020. Reservoir quality and micrite textures of microporous intervals in the Upper Cretaceous successions in the Zagros area, SW Iran. Journal of Petroleum Science and Engineering, 192, 107292.
Mehrabi, H., Rahimpour-Bonab, H., Enayati-Bidgoli, A.H., et al., 2014. Depositional environment and sequence stratigraphy of the Upper Cretaceous Ilam Formation in central and southern parts of the Dezful Embayment, SW Iran. Carbonates and Evaporites, 29, 263–278.
Adabi, M.H. & Mehmandosti, E.A.., 2008. Microfacies and geochemistry of the Ilam Formation in the Tang-E Rashid area, Izeh, SW Iran. Journal of Asian Earth Sciences, 33(3-4), 267-277.
Mohammed Sajed, O.K. & Glover, P.W.J., 2020. Dolomitization, cementation and reservoir quality in three Jurassic and Cretaceous carbonate reservoirs in north-western Iraq. Marine and Petroleum Geology, 115, 104256.
Moore, C. H. & Wade, W. J., 2013. Chapter 4 - The nature and classification of carbonate porosity. In: Moore, C. H. & Wade, W. J. (Eds.), Carbonate reservoirs, Vol. 67, pp. 51–65. Elsevier.
Poursoltani, R., Pourkermani, M., Yazdjerdi, K. & Almassian, M., 2016. Investigating the impress of the active tectonics and the rate of fractures in Ilam Formation, Fars Area, SW Iran. Open Journal of Geology, 6(6), Article ID:67804, 18 pages.
Rashid, F., Hussein, D., Glover, P.W.J., Lorinczi, P. & Lawrence, J.A., 2022. Quantitative diagenesis: Methods for studying the evolution of the physical properties of tight carbonate reservoir rocks. Marine and Petroleum Geology, 139, 105603.
Reza, M.M., 2020. Sequence stratigraphy of Albian–Campanian carbonate deposits (Sarvak and Ilam formations) in Shiraz area, Fars, SW Iran. Carbonates and Evaporites, 35, 92.
Setudehnia, A., 1978. The Mesozoic sequence in south-west Iran and adjacent areas. Journal of Petroleum Geology, 1(1), 3–42.
Soleimani, B., Ahmadi Nabi, M. & Jahani, D., 2022. Microfacies, sedimentary environment and diagenetic processes analysis of Ilam Formation in Gachsaran Oil Field, Zagross Basin. Iranian Journal of Petroleum Geology, 21, 16–32.
Tucker, M.E., 2009. Carbonate diagenesis and sequence stratigraphy. Sedimentology Review/1, August, 51–72.
Wilson, J.L., 1975. Principles of carbonate sedimentation. In: Carbonate facies in geologic history, pp. 1–19.
Zhang, K., Fang, X., Xie, Y., Guo, S., Liu, Z. & Wang, L., 2020. Diagenesis and origination of carbonate cements in deeply buried sandstones of the Eocene Es3Member, Raoyang Sag, Bohai Bay Basin, China. Geofluids, 2020.

Files

Share

How to cite

Statistics