ارزیابی پتانسیل هیدروکربن‌زایی و تاریخچه تدفین سنگ‌های مادر محتمل در میدان سلمان، شرق خلیج فارس

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه اکتشاف، دانشکده مهندسی معدن و متالورژی، دانشگاه یزد، یزد، ایران

2 گروه مهندسی نفت، دانشکده مهندسی نفت، دانشگاه صنعتی امیرکبیر، تهران، ایران

چکیده

میدان سلمان، یکی از مهم­ترین میادین تولیدی در بخش شرقی خلیج فارس محسوب می­شود که در افق­های کنگان/دالان دارای گاز و در افق­های سورمه، گدوان و داریان دارای نفت است. پژوهش حاضر به بررسی پتانسیل هیدروکربن­زایی سازندهای گورپی، سروک، کژدمی، داریان، گدوان، فهلیان، سورمه و سرچاهان در میدان سلمان با استفاده از اطلاعات پیرولیز راک­اول، انعکاس ویترینایت و نتایج مدل­سازی یک بعدی در یکی از چاه­های عمیق میدان، می­پردازد. بدین منظور 50 نمونه سنگ، بجز سازند سرچاهان، از اعماق مختلف در دو چاه، مورد آنالیز و ارزیابی قرار گرفت. نمونه­های مربوط به سازندهای سروک و سورمه به ترتیب پتانسیل هیدروکربن­زایی خوب و متوسط را نشان دادند در حالی که بقیه نمونه­ها دارای پتانسیل ضعیف بودند. مواد آلی سازند سروک دارای کروژن تیپ II و مواد آلی سازند سورمه دارای کروژن تیپ II/III بودند. بنابر انعکاس ویترینایت حاصل از پتروگرافی و مدلسازی، سازند سروک نابالغ، سازند سورمه در اوایل پنجره نفتی و سازند سرچاهان در پنجره گازی قرار دارند. نسبت تبدیل برای سازند سرچاهان، 95 درصد است در حالی که این نسبت برای سازندهای سروک و سورمه صفر می­باشد. 

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation of petroleum generation potential and burial history of probable source rocks in the Salman field, eastern part of the Persian Gulf

نویسندگان [English]

  • Ehsan Hosseiny 1
  • Ali Rahmani 2
1 Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran.
2 Department of Petroleum Engineering, Amirkabir University of Technology, Tehran, Iran
چکیده [English]

Introduction
The Persian Gulf basin is one of the most prolific and important hydrocarbon provinces in the world. The presence of rich source rocks, fractured carbonate reservoirs, effective cap rocks alongside large anticlines has led to the accumulation of large volumes of oil and gas in this area. This study investigates the hydrocarbon generation potential of probable source rocks in Salman field through using Rock Eval, vitrinite reflection and 1D model results in one of deepest wells.
Materials and methods
In this study, Rock-Eval 6 and Vitrinite reflection were used to evaluate the hydrocarbon generation potential of source rock samples. Accordingly, 50 and 18 rock samples from Gurpi, Sarvak, Kazhdumi, Dariyan, Gadvan, Fahliyan and Surmeh formations in two wells of Salman were analyzed, respectively. Moreover, one-dimensional modeling of burial history was performed by using Petromed software (2011-Schlumberger) on well B of Salman field.
Results and discussion
The TOC of the samples is between 0.16 and 2.83%, of which about 90% have a value less than one. Petroleum potential index (S1+S2) varies from 0.43 to 17.5 mg HC/gr Rock. The highest TOC and petroleum potential index values are related to Sarvak samples. Surmeh samples indicate fair petroleum generation potential while the rest of the samples indicate poor petroleum generation potential. Based on HI, Sarvak and Surmeh samples have kerogen type II and II/III respectively. Vitrinite reflectance values range from 0.3 to 0.55, indicating that the samples are in the immature to early mature stages. One-dimensional modeling was performed to determine the burial and thermal history of the Sarchahan, Surmeh and Sarvak source rocks and the time of hydrocarbon generation at well B. The temperature history of the layers in the sedimentary basin is estimated by model and calibrated by vitrinite reflections. According to estimated vitrinte reflection (Sweeney and Burnham model), Sarvak Formation is immature and Surmeh Formation is early mature. The Sarchahan Formation is currently in gas window. This formation has entered the peak of the oil window since 157 million years ago and entered the gas window since 75 million years ago.
Conclusions
Geochemical assessment of different formations in Salman field confirmed that Sarvak, Surmeh and Sarchahan formations are the most important source rocks in the eastern part of the Persian Gulf. Sarchahan source rock is in the gas window and has produced 95% of its potential so far. Organic matters of Sarvak and Surmeh formations have kerogen type II and II/III, respectively. Sarvak Formation is immature and Surmeh Formation is in the early oil window. Although Sarvak Formation is immature in Salman field, it could generate high amounts of hydrocarbon by increasing depth in the eastern parts of Salman oil fields.

کلیدواژه‌ها [English]

  • Hydrocarbon generation potential
  • Burial history
  • Source rock
  • Thermal modeling
  • Salman field
-Abu-Ali, M.A., Franz, U.A., Shen, J., Monnier, F., Mahmoud, M.D. and Chambers, T.M., 1991. Hydrocarbon generation and migration in the Paleozoic Sequence of Saudi Arabia. Society of Petroleum Engineers (SPE) Middle East Oil Show, Manama, Bahrain, p. 345-356.
-Al-Hajeri, M.M. and Al-Saeed, M., 2009. Basin and Petroleum System Modeling. Schlumberger, Oilfield Review, v. 21(2).
-Alizadeh, B., Alipour, M., Chehrazi, A. and Mirzaie, S., 2017. Chemometric classification and geochemistry of oils in the Iranian sector of the southern Persian Gulf Basin. Organic Geochemistry, v. 111, p. 67-81.
-Behar, F., Vandenbroucke, M., Tang, Y., Marquis, F. and Espitalie, J., 1997. Thermal cracking of kerogen in open and closed systems: determination of kinetic parameters and stoichiometric coefficients for oil and gas generation. Organic Geochemistry, v. 66, p. 321-339.
-Beydoun, Z.R., 1991. Arabian plate hydrocarbon geology and potential- A plate tectonic approach American Association of Petroleum Geologists Bulletin Studies in Geology, v. 33, 77 p.
-Bordenave, M.L. and Burwood, R., 1990. Source rock distribution and maturation in the Zagros belt; provenance of the Asmari and Bangestan reservoir oil accumulations. Organic Geochemistry, v. 16, p. 369-387.
-Bordenave, M.L. and Hegre, J.A., 2010. Current distribution of oil and gas fields in the Zagros Fold Belt of Iran and contiguous offshore as the result of the petroleum systems. In: Leturmy, P., Robin, C. (Eds.), Tectonic and Stratigraphic Evolution of Zagros and Makran during the Mesozoic–Cenozoic. Geological Society Special Publication 330, London, p. 291-353.
-Buerberry, C.M., Jackson, C.A.L. and Cosgrove, J.W., 2011. Late Cretaceous to Recent Deformation Related to Inherited Structures and Subsequent Compression within the Persian Gulf: A 2D Seismic Case Study. Journal of the Geological Society, v. 168, p. 485-498.
-Cole, G.A., Abu-Ali, M.A., Aoudeh, S.M., Carrigan, M.J., Chen, H.H., Colling, E.L., Gwathney, W.J., Al-Hajii, A.A., Halpern, H.I., Jones, P.J., Al-Sharidi, S.H. and Tobey, M.H., 1994. Organic geochemistry of the Paleozoic petroleum system of Saudi Arabia. Energy Fuels, v. 8, p. 1425-1442.
-Dow, W.G., 1977. Kerogen studies and geological interpretations. Journal of Geochemical Exploration, v. 7, p. 77-99.
-Espitalié, J., Laporte, J.L., Madec, M., Marquis, F., Leplat, P. and Paulet, J., 1977. Méthode rapide de caractérisation des roches mères, de leur potential pétrolier et de leur degree d’évolution. Revue de l’Institut Français du Pétrole, v. 32, p. 23-45.
-Fathi Mobarakabad, A., Bechtel, A., Gratzer, R., Mohsenian, E. and Sachsenhofer, R.F., 2011. Geochemistry and origin of crude oils and condensates from the central Persian Gulf, offshore Iran, Journal of Petroleum Geology, v. 34, p. 261-275.
-Ghavidel-syooki, M., Álvaro, J.J., Popov, L., Ghobadi Pour, M., Ehsani, M.H. and Suyarkova, A., 2011. Stratigraphic evidence for the Hirnantian (latest Ordovician) glaciation in the Zagros Mountains, Iran. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 307, p. 1-16.
-Ghazban, F., 2007. Petroleum Geology of Persian Gulf. Tehran, Iran: Tehran University.
Grunau, H.R., 1977. Generation, migration entrapment and retention of hydrocarbons in the Middle East. Pet. Time, p. 33-43.
-Hassan, T.H. and Azer, S., 1985. The occurrence and origin of oil in Offshore Abu Dhabi. In: Middle East Technical Conference and Exhibition. Society of Petroleum Engineers, Bahrain, p. 143-160.
-Hosseiny, E., Rabbani, A.R. and Moallemi, S.A., 2016. Source rock characterization of the Cretaceous Sarvak Formation in the eastern part of the Iranian sector of Persian Gulf. Organic Geochemistry, v. 99, p. 53-66.
-Hosseiny, E., Rabbani, A.R. and Moallemi, S.A., 2017. Oil families and migration paths by biological markers in the eastern Iranian sector of Persian Gulf. Journal of Petroleum Science and Engineering, v. 150, p. 54-68.
-Kashfi, M.S., 1992. Geology of the Permian “super-giant” gas reservoirs in the greater Persian Gulf area. Journal of Petroleum Geology, v. 15, p. 465-480.
-Langford, F.F. and Blanc-Valleron, M.M., 1990. Interpreting Rock-Eval pyrolysis data using graphs of pyrolyzable hydrocarbons vs. total organic carbon. American Association of Petroleum Geologists Bulletin, v. 74, p. 799-804.
-Peters, K.E. and Cassa, M.R., 1994. Applied source rock geochemistry. In: Magoon, L.B., Dow, W.G. (Eds.), The Petroleum System – From Source to Trap. American Association of Petroleum Geologists Memoir, v. 60, p. 93-120.
-Rabbani, A.R., 2008. Geochemistry of crude oil samples from the Iranian sector of the Persian Gulf. Journal of Petroleum Geology, v. 31, p. 303-316.
-Rabbani, A.R., Kotarba, M.J., Baniasad, A.R., Hosseiny, E. and Wieclaw, D., 2014. Geochemical characteristics and genetic types of the crude oils from the Iranian sector of the Persian Gulf. Organic Geochemistry, v. 70, p. 23-43.
-Saberi, M.H., Rabbani, A.R. and Ghavidel-syooki, M., 2016. Hydrocarbon potential and palynological study of the Latest Ordovician – Earliest Silurian source rock (Sarchahan Formation) in the Zagros Mountains, southern Iran. Marine and Petroleum Geology, v. 71, p. 12-25.
-Sharland, P.R., Archer, R., Casey, D.M., Davies, R.B., Hall, S.H., Heward, A.P., Horbury, A.D. and Simmons, M.D., 2001. Arabian Plate Sequence Stratigraphy. Gulf Petrolink, Manama, Bahrain.
-Sweeney, J. and Burnham, A. K., 1990. Evaluation of a simple model of vitrinite reflectance based on chemical kinetics: American Association of Petroleum Geologist Bulletin, v. 74, p. 1559-1570.
-Taylor, G.H., Teichmüller, M., Davis, A., Diessel, C.F.K., Littke, R. and Robert, P., 1998. Organic Petrology. Gebrüder Borntraeger, Berlin, Stuttgart.
-Tissot, B.P. and Welte, D.H., 1984. Petroleum formation and occurrence, Springer Verlag, 699 p.
-Waples, D.W., Kamata, H. and Suizu, M., 1992. The art of maturity modeling: Part 1. Finding a satisfactory geological model. American Association of Petroleum Geologists Bulletin, v. 76, p. 31‌-46.
-Welte, D.H. and Yalcin, M.N., 1988. Basin modelling; a new comprehensive method in petroleum geology. Organic Geochemistry, v. 13, p. 141-151.
-Wygrala, B.P., 1989. Integrated Study of an Oil Field in the Southern Po Basin, Northern Italy: Ph.D. dissertation, University of Cologne, 217 p.
-Yalcin, M.N., Littke, R. and Sachsenhofer, R.F., 1997. Thermal history of sedimentary basins. In: Welte, D.H., Horsfield, B., Baker, D.R. (Eds.), Petroleum and basin evolution. Springer, p. 3-70.