Structural Modeling and Estimation of Tectonic Stresses at Lali Oilfield in Dezful Embayment
Subject Areas : Geoscience Fields in relation with Petroleum GeologyNasrin kianizadeh 1 , Behzad Zamani 2 , Rahym khadkhodayi 3 , Hoseyn Talebi 4
1 -
2 -
3 -
4 -
Keywords: Fault modeling Prtrel, Orientation tension fracture Dencity log Lali oil field Poroelastic equations,
Abstract :
Structural geological study is one of the most important stages of an oilfield exploration and production (E&P) program, since a knowledge of existing structures can play a fundamental role in the oilfield development plan. The main purpose of this study is to create three-dimensional (3D) structural models to determine direction of tectonic stresses at Lali oilfield using subsurface geophysical data. The study area is located within the so-called Dezful Embayment (northern Khuzestan Province, Iran). Accordingly, in order to provide a 3D model of the reservoir, geostatistical tools in Petrel Software were utilized. Incorporating density log data into several coded formulations in MS Excel Software, the reservoir had its modulus of elasticity calculated. Subsequently, maximum and minimum horizontal stresses were calculated using poroelastic equations. Fault modeling results showed that, fault dip increases with increasing the depth towards the center of the field. Obtained values of stress using the poroelastic equations show that σ_H>σ_h>σ_v, confirming a regional reverse stress regime, which is consistent with previous studies in this area. Also, the formal stress ratios (Φ = (σ2-σ3) / (σ1-σ3)) obtained from poroelastic equations and inverse analysis method were found to be well-correlated across the area. Finally, average azimuth of the reverse faults on the southern limb (as calculated by Petrel) and the fractures on the limb (as obtained from FMI images and core samples) were found to be N305 and N315, respectively (average = N310). Thus, N040E was inferred to be the average direction of principal stress, i.e. principal stress is mostly directed along a NE-SW axis (perpendicular to the general trend of Zagros Orogeny); this is probably a result of the activities of youngest Zagros orogeny phase. The agreement between the obtained principal stress directions by fractures, faults, and focal mechanism of earthquakes across the World Stress Map (WSM) confirms the validity of this study.
منابع
-[1]دلارام. و، رسولی.ا، 1386، تأثير تنش هاي برجا بر مكانيسم گسيختگي چاه هاي نفتي، سومین کنفرانس سنگ ایران.#
-[2] رمضانی.ع، علوی. س. ا، حاجی علی بیگی.ح، طالبی.ح، 1389، تحلیل ساختاری و شکستگیهای میدان نفتی لالی، پایان نامه کارشناسی ارشد، رشته تکتونیک، دانشگاه علوم زمین، دانشگاه شهید بهشتی،140.#
-[3]زمانی. ب، کیانی زاده. ن ، پرهیزکاری. ح،1393، بررسي وضعيت تنش نوزمين ساختي زاگرس با جدایش تنشها، علوم زمین.#
-[4]ژئوفیزیک کاربردی، ترجمه حسین زمردیان و حسین حاجب حسینی،1984، انتشارات دانشگاه تهران، جلد اول صفحه 312-302.#
-[5]طالبی، ح. نریمانی، ح. 1388. ارتباط ساختاري تاقديسهاي زيلويي، لالي و كارون. گزارشات شركت ملي مناطق نفت خيز جنوب.#
- [6]کلاگری، ع. 1389. اصول اکتشافات ژئوفیزیکی. کلاگری. 485 صفحه.#
-[7]محمودی، ح.1391. مطالعه تکمیلی و تهیه مدل زمینشناسی مخزن بنگستان میدان لالی. گزارش شرکت مناطق نفتخیز جنوب.#
-[8]مطیعی.ه ، 1374، زمینشناسی نفت زاگرس، انتشارات سازمان زمینشناسی کشور، جلد اول 589. #
[9]- Akbar, M. and Sapru, A., 1994, October. In-situ stresses in the subsurface of Arabian Peninsula and their effect on fracture morphology and permeability. In 6th Abu-Dhabi International Petroleum Exhibition and Conference (pp. 16-19).#
[10]- Angelier, J, 2002, Inversion of earthquake focal mechanisms to obtain the seismotectonic stress (a new method free of choice among nodal planes) IV, Geophys, J. Int, 150: 588-609.#
[11]- Aadnoy, B.S., 1990. Inversion technique to determine the in-situ stress field from fracturing data. Journal of Petroleum Science and Engineering, 4(2), pp.127-141.#
[12]- Bachmanov, D.M., Trifonov, V.G., Hessami, K.T., Kozhurin, A.I., Ivanova, T.P., Rogozhin, E.A., Hademi, M.C. and Jamali, F.H., 2004. Active faults in the Zagros and central Iran. Tectonophysics, 380(3), pp.221-241.#
[13]- Barnett, J.A., Mortimer, J., Rippon, J.H., Walsh, J.J. and Watterson, J., 1987. Displacement geometry in the volume containing a single normal fault. AAPG Bulletin, 71(8), pp.925-937.#
[14]- Blanton, T.L. and Olson, J.E., 1997, January. Stress magnitudes from logs: effects of tectonic strains and temperature. In SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers.#
[15]- Fjar E, Holt RM, Raaen AM, Risnes R, Horsrud P, 2008, Petroleum related rock mechanics, Elsevier; 2008 Jan 4.#
[16]- Geoscience central, Iran, Ahvaz. 2010. LL26. Emi quick look report.#
[17]- Hajialibeigi, H., 2011. Signatures of the Balarud Deep Seated Fault Zone in Khushab Anticline, SW Iran, An Integrated Study. Journal of Sciences, Islamic Republic of Iran, 22(1), pp.33-81.#
[18]- Heidbach, O., Tingay, M., Barth, A., Reinecker, J., Kurfeß, D. and Müller, B., 2010. Global crustal stress pattern based on the World Stress Map database release 2008. Tectonophysics, 482(1), pp.3-15.#
[19]- Hosseini, F. Ashtiani Abdi, H. Shiroodi, S, K., 2012, Wellbore stability study of sarvak-Kazhdomi- Darian Salman field, IOOC Technical Affairs, Geology Department.#
[20]- Horn, M.K. , 1991, Play concepts for horizontal drilling, In Fritz, R.D. et al. (eds), Geological Aspects of Horizontal drilling, American Association of Petroleum Geologists Education Course Note Series, v. 33, p. 189-323.#
[21]- Carvajal Jiménez, J.M., Valera Lara, L.C., Rueda, A. and Saavedra Trujillo, N.F., 2007. Geomechanical wellbore stability modeling of exploratory wells-study case at middle Magdalena Basin. CT&F-Ciencia, Tecnología y Futuro, 3(3), pp.85-102.#
[22]- Jones, R.R., McCaffrey, K.J.W., Clegg, P., Wilson, R.W., Holliman, N.S., Holdsworth, R.E., Imber, J. and Waggott, S., 2009. Integration of regional to outcrop digital data: 3D visualisation of multi-scale geological models. Computers & Geosciences, 35(1), pp.4-18.#
[23]- Kaufmann, O. and Martin, T., 2008. 3D geological modelling from boreholes, cross-sections and geological maps, application over former natural gas storages in coal mines. Computers & Geosciences, 34(3), pp.278-290.#
[24]- Kim, Y.S. and Sanderson, D.J., 2005. The relationship between displacement and length of faults: a review. Earth-Science Reviews, 68(3), pp.317-334.#
[25]- Zoback, M.D., Barton, C.A., Brudy, M., Castillo, D.A., Finkbeiner, T., Grollimund, B.R., Moos, D.B., Peska, P., Ward, C.D. and Wiprut, D.J., 2003. Determination of stress orientation and magnitude in deep wells. International Journal of Rock Mechanics and Mining Sciences, 40(7), pp.1049-1076.#
[26]- Zare, M.R., Shadizadeh, S.R. and Habibnia, B., 2010, January. Mechanical stability analysis of directional wells: a case study in Ahwaz oilfield. In Nigeria Annual International Conference and Exhibition. Society of Petroleum Engineers.#
[27]- Mitra, S., 1990. Fault-propagation folds: geometry, kinematic evolution, and hydrocarbon Traps (1). AAPG Bulletin, 74(6), pp.921-945.#
[28]- Peter J.D., Paulo J.R.,2007, Model-based Geostatistics, Springer Science, Library of Congress.#
[29]- Plumb, R., Edwards, S., Pidcock, G., Lee, D. and Stacey, B., 2000, January. The mechanical earth model concept and its application to high-risk well construction projects. In IADC/SPE Drilling Conference. Society of Petroleum Engineers.#
[30]- Schlumberger,2008, Petrel Introduction course, Petrel, 555p.#
[31]- Schlumberger, Swismic-to-Simulation Software, 2009, Property Modeling Course, 503p.#
[32]- Sanaee, R., Shadizadeh, S.R. and Riahi, M.A., 2010. Determination of the stress profile in a deep borehole in a naturally fractured reservoir. International Journal of Rock Mechanics and Mining Sciences, 47(4), pp.599-605. #
[33]- Tingay, M.R., Hillis, R.R., Morley, C.K., King, R.C., Swarbrick, R.E. and Damit, A.R., 2009. Present-day stress and neotectonics of Brunei: Implications for petroleum exploration and production. AAPG Bulletin, 93(1), pp.75-100.#
[34]- Tingay, M., Müller, B., Reinecker, J., Heidbach, O., Wenzel, F. and Fleckenstein, P., 2005. Understanding tectonic stress in the oil patch: The World Stress Map Project. The Leading Edge, 24(12), pp.1276-1282.#
[35]- Xiubin, L.I.N., Hanlin, C.H.E.N., CHENG, X., Zhongyan, S.H.E.N., Shufeng, Y.A.N.G. and Ancheng, X.I.A.O., 2010. Conceptual models for fracturing in fault related folds. Mining Science and Technology (China), 20(1), pp.103-108.#
[36]- Yaghoubi, A.A. and Zeinali, M., 2009. Determination of magnitude and orientation of the in-situ stress from borehole breakout and effect of pore pressure on borehole stability—Case study in Cheshmeh Khush oil field of Iran. Journal of Petroleum Science and Engineering, 67(3), pp.116-126.#