بررسی پارامترهای هندسی و کینماتیکی تاقدیس سرکان، لرستان، غرب ایران
محورهای موضوعی :
رضا علی پور
1
( گروه زمین‌شناسی، دانشکده علوم‌زمین، دانشگاه شهید بهشتی)
امیرحسین صدر
2
( دانشگاه بوعلی‌سینا همدان)
سمیرا شه‌مرادی
3
(دانشگاه بوعلی‌سینا همدان)
عارف شمس‌زاده
4
(دانشگاه شیراز)
کلید واژه: پارامتر هندسی, تاقدیس, سرکان, زاگرس, لرستان.,
چکیده مقاله :
تاقدیس سرکان در پهنه رسوبی - ساختاری لرستان و در کمربند چین‌خورده رانده زاگرس قرار می‌گیرد. هندسه و کینماتیک چین‌ها در این پهنه توسط گسل‌های راندگی و سطوح جدایشی کنترل می‌شود. سازندهای رخنمون یافته در این تاقدیس، سازندهای کرتاسه بالایی و سنوزوئیک هستند. در این پژوهش، با استفاده از تفسیر نیمرخ‌های لرزه‌ای و رسم چهار نیمرخ ساختاری و محاسبه پارامترهای هندسی، به بررسی هندسه و تحلیل سبک دگرریختی تاقدیس و نقش سطوح جدایشی بر سبک چین‌خوردگی آن پرداخته شده است. ساختار این تاقدیس تحت‌تاثیر دو سطح جدایش قرار می‌گیرد که سازند فلیشی امیران به‌عنوان سطح جدایش بالایی و سازند شیلی گرو نیز به‌عنوان سطح جدایش میانی است. ضخامت زیاد سطح جدایش بالایی باعث جابجایی به سمت جنوب‌غرب محور تاقدیس سطحی نسبت به تاقدیس عمقی شده است. بررسی‌های انجام شده بر روی پارامترهای هندسی و نیمرخ‌های ساختاری تاقدیس سرکان نشان‌دهنده نامتقارن و استوانه‌ای بودن این تاقدیس است و از لحاظ فشردگی و نسبت ابعادی به ترتیب در رده، باز تا ملایم و پهن قرار می‌گیرد.
The Sarkan anticline is located in the Lurestan sedimentary-structural zone and in the Zagros fold and thrust belt. Geometry and kinematic of the fold of this zone are controlled by thrust faults and detachment levels. The exposed formations in this anticline are the upper Cretaceous and Cenozoic formations. In this research, geometry and deformational style analysis of the anticline and role of the detachment levels on folding style have been investigated using drawing four structural cross-sections, interpretation of the seismic profiles and calculation of geometric parameters. The structure of this anticline is affected by two detachment horizon, which is the flysch Amiran, and shaly Garu formations as the upper and middle detachment levels, respectively. The high thickness of the upper detachment level caused displacement of the surface anticline axis to the SW with respect to the deep anticline axis. The study of geometrical parameters and structural cross-sections of the Sarkan anticline exhibit that this structure is an asymmetric and noncylindrical anticline, and from tightness and aspect ratio view is ranked in the open to gentle and wide category, respectively.
شمس‌زاده، ع.، علوی، ا.، ولی‌نژاد، م. و توکلی یرکی، م.، 1396. سبک چین‌خوردگی و پیچیدگی‌های ساختاری در زیرپهنه‌ی لرستان مرکزی (مطالعه موردی یکی از میادین نفتی ناحیه). ماهنامه علمی - ترویجی اکتشاف و تولید نفت و گاز، 144، 48-53.
مطیعی، هـ.، 1374. چینه‌شناسی زاگرس. انتشارات سازمان زمین‌شناسی و اکتشافات معدنی ایران،540.
Agard, P., Omrani, J., Jolivet, L. and Mouthereau, F., 2005. Convergence history across Zagros (Iran): constraints from collisional and earlier deformation. International Journal of Earth Sciences, 94, 401-41.
Alavi, M., 1994. Tectonics of the Zagros orogenic belt of Iran: new data and interpretations. Tectonophysics, 229, 211–238.
Alavi, M., 2007. Structures of the Zagros fold thrust belt in Iran. American Journal of Science, 307, 1064–1095.
Berberian, M., 1995. Master Blind thrust faults hidden under the Zagros folds: Active basement tectonics and surface morphotectonics. Tectonophysics, 241, 193-224.
Berberian, M. and King, G.C.P., 1981. Towards a paleogeography and tectonic evaluation of Iran. Canadian Journal of Earth Sciences, 18, 210–265.
Blanc, E. P., Allen, M. B., Inger, S. and Hassani, H., 2003. Structural styles in the Zagros simple folded zone, Iran. Journal of the Geological Society, 160, 3, 401-412.
Dewey, J.F., Pitman, W.C., Ryan, W.B.F. and Bonnin, J., 1973. Plate tectonics and the evolution of the Alpine System. Geological Society of America Bulletin, 84, 3137-3180.
Falcon, N.L., 1969. Problems of the relationship between surface structure and deep displacements illustrated by the Zagros Range. Geological Society, London, Special Publications, 3, 1, 9-21.
Farzipour-Saein, A., Yassaghi, A., Sherkati, S. and Koyi, H., 2009a. Mechanical stratigraphy and folding style of the Lurestan region in the Zagros Fold Thrust Belt, Iran. Journal of the Geological Society, 166, 1101-1115.
Farzipour-Saein, A., Yassaghi, A., Sherkati, S. and Koyi, H., 2009b. Basin evolution of the Lurestan region in the Zagros fold and thrust belt. Iran. Journal of Petroleum Geology, 32, 1, 5-19.
Golonka, J., 2004. Plate tectonic evolution of the southern margin of Eurasia in the Mesozoic and Cenozoic. Tectonophysics, 381, 1, 235-273.
Hardy, S. and Poblet, J., 1995. The velocity description of deformation. Paper 2: sediment geometries associated with fault-bend and fault-propagation folds. Marine and Petroleum Geology, 12, 2, 165-176.
Haynes, S.J. and McQuillan, H., 1974. Evolution of the Zagros suture zone, southern Iran. Geological Society of America Bulletin, 85, 5, 739-744.
Hessami, K., Koyi, H.A., Talbot, C.J., Tabasi, H. and Shabanian, E., 2001. Progressive unconformities within an evolving foreland fold–thrust belt, Zagros Mountains. Journal of the Geological Society, 158, 6, 969-981.
Homke, S., Verges, J., Garces, M., Emami, H. and Karpuz, R., 2004. Magnetostratigraphy of Miocene–Pliocene Zagros foreland deposits in the front of the Push-e Kush arc (Lurestan Province, Iran). Earth and Planetary Science Letters, 225, 3, 397-410.
Homza, T.X. and Wallace, W.K., 1995. Geometric and kinematic models for detachment folds with fixed and variable detachment depths. Journal of Structural Geology, 17, 575-588.
Hudleston, P.J. and Lan, L., 1993. Information from fold shapes. Journal of Structural Geology, 15, 3, 253-264.
James, G.A. and Wynd, J.G., 1965. Stratigraphic nomenclature of Iranian oil consortium agreement area. AAPG Bulletin, 49, 12, 2182-2245.
Jamison, W.R., 1987. Geometric analysis of fold development in overthrust terrenes. Journal of Structural Geology, 9, 207-219.
Koop, W.J. and Stoneley, R., 1982. Subsidence history of the Middle East Zagros Basin, Permian to Recent. Philosophical Transactions of the Royal Society of London, Series A, 05, 149–168.
Koyi, H. A., Sans, M. and Bahroudi, A., 2004. Modelling the deformation front of fold-thrust belts containing multiple weak horizons. Bollettino di Geofsica Teorica ed Applicata, 45, 101-103.
Marrett, R. and Bentham, P.A., 1997. Geometric analysis of hybrid fault-propagation/detachment folds. Journal of Structural Geology, 19, 3-4, 243-248.
McClay, K.R., Whitehouse, P.S., Dooley, M. and Richards, M., 2004. 3D evolution of fold and thrust belts formed by oblique convergence. Marine and Petroleum Geology, 21, 857–877.
McQuarrie, N. and Van Hinsbergen, D.J., 2013. Retrodeforming the Arabia-Eurasia collision zone: Age of collision versus magnitude of continental subduction. Geology, 41, 3, 315-318.
McQuarrie, N., 2004. Crustal scale geometry of the Zagros fold–thrust belt, Iran. Journal of Structural Geology, 26, 3, 519-535.
Mohajjel, M. and Fergusson, C.L., 2014. Jurassic to cenozoic tectonics of the zagros orogen in northwestern Iran. International Geology Review, 56, 3, 263-287.
Mouthereau, F., Lacombe, O. and Verges, J., 2012. Building the Zagros collisional orogen: timing, strain distribution and the dynamics of Arabia/Eurasia plate convergence. Tectonophysics, 532, 27–60.
Pirouz, M., Simpson, G., Bahroudi, A. and Azhdari, A., 2011. Neogene sediments and modern depositional environments of the Zagros foreland basin system. Geological Magazine, 148, 5–6, 838–853.
Poblet, J.A. and McClay, K.R., 1996. Geometry and kinematics of single layer detachment folds. AAPG Bulletin, 80, 1085-1109.
Ramsay, J.G., 1967. Folding and Fracturing of Rocks. McGraw-Hill Companies, 568.
Ramsay, J.G., and Huber, M.I., 1987. The Techniques of Modern Structural Geology, 2. Academic press, 697.
Salvini, F. and Storti, F., 2002. Three-dimensional architecture of growth strata associated to fault-bend, fault-propagation, and decollement anticlines in non-erosional environments. Sedimentary Geology, 146, 1, 57-73.
Sepehr, M., Cosgrove, J.W. and Moieni, M., 2006. The impact of cover rock rheology on the style of folding in the Zagros fold-thrust belt. Tectonophysics, 427, 265-281.
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, 535-554.
Sherkati, S., Letouzey, J. and Frizon de Lomotte, D., 2006. Central Zagros fold-thrust belt (Iran): New insights from seismic data, field observation, and sandbox modeling. Tectonics, 25, 1-27.
Stocklin, J., 1968. Structural history and tectonics of Iran: A review. American Association of Petroleum Geologists Bulletin, 52, 1229–1258.
Suppe, J., 1985. Principles of Structural Geology. Englewood Cliffs New Jersey, Prentice Hall, 537.
Takin, M., Akbari, Y. and Macleod, J.H., 1970. Pul-e Dukhtar Geological Compilation Map 1: 100,000 (Sheet 20812 E). National Iranian Oil Company (NIOC).
Takin, M., 1972. Iranian geology and continental drift in the Middle East. Nature, 235, 147-150.
Tamagawa, T., Matsuoka, T. and Tamura, Y., 1998. Geometrical shape of fault-bend folding with simple shear deformation in the thrust sheet (in Japanese). Geoinformatics (Joho Chishitsu, Osaka), 9, 3-11.
Tanner, P.G., 1989. The flexural-slip mechanism. Journal of Structural Geology, 11, 6, 635-655.
Verges, J., Saura, E., Casciello, E., Fernandez, M., Villasenor, A., Jimenez-Munt, I. and Garcia-Castellanos, D., 2011. Crustalscale cross-sections across the NW Zagros belt: Implications for the Arabian margin reconstruction. Geological Magazine, 148, 739–761.
Wallace, W. K. and Homza, T.X., 2004. Detachment folds versus fault-propagation folds and their truncation by thrust faults. In: McClay, K.R. (ed.), Thrust tectonics and hydrocarbon systems. American Association of Petroleum Geologists Bulletin, memoir, 82, 324-355.
Ziegler, P.A. and Stampfli, G.M., 2001. Late Paleozoic-Early Mesozoic plate boundary reorganization: collapse of the Variscan orogen and opening of Neotethys. In: Cassinis, R. (Ed.), the Continental Permian of the Southern Alps and Sardinia (Italy) Regional Reports and General Correlations, Ed. 25. Annali Museo Civico Science Naturali, Brescia, 17–34.