Kinematics and Geometrical Study of Dara anticline Fractures, Dezful Embayment


Department of Geology, University of Isfahan


    Asmari Formation, as the reservoir rook of almost three-quarters of the explored oil in the south west of Iran, has a great importance. The quality of the Asmari reservoirs is often affected by the fracture systems. In this study, aiming to look at the fracture patterns in the Asmari reservoirs, Dara anticline, in southern Dezful embayment, with extent outcrop of the Asmari Formation has been focused. The fractures associated with Dara anticline and its adjacent faults, including kamaryj fault segment (as a part of the kazeroon fault) were identified by remote sensing approach. Accordingly, in Dara anticline, the fracture set of A, with AZ140° -150° orientation (as the longitudinal fracture set), , the fracture set of B, with AZ40°-60° orientation (as transverse  fracture set), the fracture sets of C and D, with AZ0°-10° and AZ80°-90° orientation, respectively  (as conjugated  fracture sets), were identified. Indeed, the fractures associated with kamaryj fault segment, with Ŕ, T, P and R components were identified as well. Fracture intensity and density distribution of Dara anticline demonstrates that, fractures in the north- eastern limb and hinge zone are more than the southwest limb which is due to the presence of fault with a N35W trend at the northeast limb of this anticline. Also, the increase in intensity and density in hinge zone is because of higher flexure in that part, which leads to an increase in fracture generation at this part of the anticline. Investigating the length of fractures in different parts of the Dara anticline revealed that the frequency of fractures increases exponentially when the length of fracture is reduced. Finally, geometrical- kinematical pattern of fractures and also their distribution pattern is very essential for hydrocarbon exploration- extraction within the Asmari reservoir throughout the area and other parts of the Zagros.


آقانباتی.ع.، 1385، زمین شناسی ایران،ص586، سازمان زمین شناسی و اکتشافات معدنی کشور تهران.
حاجی.ع.، رحیمی.ب.، 1389، الگو‌های آماری و فراکتالی سیستم‌های شکستگی منطقه تکنار- ایران مرکزی، فصل نامه علوم دانشگاه تهران، جلد سی و ششم، شماره 1، ص 136-129.
ظهراب زاده.م.، 1388، تحلیل سیستماتیک شکستگی‌های مخزن آسماری در یکی از میادین نفتی جنوب غرب ایران، مجله اکتشاف و تولید، شماره62، ص46.
سنجری.س، 1390، راهنمای کاربردی Arc Gis10، ص344، انتشارات عابد.
قنادیان.م.، رحیمی.ب.، حسینی.ک.، شبان.ع.، 1390، بررسی الگوی شکستگی‌های سازند مزدوران، شمال غرب روستای مزدوران، شرق کپه داغ، سی امین گردهمایی علوم زمین، سازمان زمین شناسی و اکتشافات معدنی کشور.
مطیعی.ه.، 1374، زمین شناسی نفت زاگرس، دو جلد، طرح تدوین کتاب زمین شناسی ، شماره 25، ص1009.
Abdollahie Fard, I., Braathen, A., Mokhtari, M., Alavi, S. A., 2006,  Interaction of the Zagros Fold–Thrust Belt and the Arabian-type, deep-seated folds in the Abadan Plain and the Dezful Embayment, SW Iran, Petroleum Geoscience, Vol: 12, P: 347–362.
Alavi, M., 2004, Regional stratigraphy of the Zagros fold-thrust belt of Iran and its proforeland evolution, American journal of Science, Vol: 304, No: 1, P: 1-20
Bartlett, W.L., Friedman, M., Logan, J.M., 1981, Experimental folding and faulting of rocks under confined pressure. Part IX. Wrench faults in limestone layers, Tectonophysics, Vol: 79, P: 255-277.
Berberian, M., King, G.C.P., 1981, Towards a paleogeography and tectonic evolution of Iran, Canadian journal of earth sciences, Vol: 18, No: 2, P: 210-265.‏
Bourne, S.J., Bauckmann, F., Rijkels, L., Stephenson, B.J., Weber, A., Willemse, E.J.M., 2000, Predictive Modeling of Naturally Fractured Reservoirs Using Geomechanism and Flow Simulation, 9th Abu Dhabi International Petroleum Exhibition and Conference (Abu Dhabi, UAE), p: 10.
Ekneligoda T. C., Henkel H., 2006, The spacing calculator software-A Visual Basic program to calculate spatial properties of lineaments, Journal of Computers & Geosciences, Vol: 32, No: 5, P: 673- 680.
Falcon, N.L., 1974, Southern Iran: Zagros mountains. In: Spencer A (Ed) Mesozoic–Cenozoic Orogenic Belts, Geological Society of London, Special Publication, Vol: 41, P: 99–211.
Farzipour-Saein, A., Yassaghi, A., Sherkati, Sh., Koyi, H., 2009, Basin evolution of the Lurestan region in the Zagros fold-and-thrust belt, Iran, Journal of Petroleum Geology, Vol: 32, P: 5-19.
Fischer, M.P., Wilkerson, M.S., 2000, Predicting the orientation of joints from fold shape: results of pseudo-three-dimensional modeling and curvature analysis, Geology Vol: 28, P: 15–18.
Heydari, E., Hassanzadeh, J., Wade, W. J., Ghazi, A. M., 2003, Permian-Triassic boundary interval in the Abadeh section of Iran with implications for mass extiontion. Part 1. Sedimentology: Palaeogeography, Palaeoclimatology, Palaeoecology, Vol: 193, P: 405-423.
James, G.A., Wynd, J.G., 1965, Stratigraphic nomenclature of Iranian oil consortium agreement area, AAPG Bulletin, Vol: 49, No: 12, P: 2182-2245.
Mobasher, K., Babaie, H. A., 2008, Kinematic significance of fold-and fault-related fracture systems in the Zagros mountains, southern Iran, Tectonophysics, Vol: 451, P: 156-169.
Price, N.J., 1966, Fault and joint development in brittle and semi- brittle rooks, Pergamon press, oxford, 176p.
Sherkati, Sh., Letouzey, J., 2004, Variation of structural style and basin evolution in the central Zagros (Izeh zone and Dezful Embayment), Iran, Marine and Petroleum Geology, Vol: 21, No: 5, P: 535-554.‏
Sylvester, A.G., 1988, Strike-slip faults, Bulletin of Geological Society of America, Vol: 100, P: 1666-1703.
Talbot, C.J., Alavi, M., 1996, The past of a future syntaxis across the Zagros. Geological Society, London, Special Publications, Vol: 100, No: 1, P: 89-109.‏
Xypolias, P., Koukouvelas, I.K., 2004, Fault trace parameters as a tool for analyzing remotely sensed fault arrays: An example from the eastern Gulf of Corinth, Greece", International Journal of Remote Sensing, Vol: 25, No: 21, P: 4685-4699