1
دانشکده علوم زمین، دانشگاه تحصیلات تکمیلی علوم پایه زنجان، زنجان، ایران
2
گروه زمین شناسی، دانشگاه بینالمللی امام خمینی (ره)، قزوین، ایران
چکیده
حوضه رسوبی ماهنشان- میانه یک حوضه باریک در جنوب شهرستان میانه و خاور شهرستان ماهنشان است که روند ساختارهای اصلـی چیـن و راندگـی لایههای سازند قرمز بالایی درون آن با راستای کشیدگی شمال -باختر- جنوب خاور حوضه همخوان است. با توجه به جایگاه این پهنه در مرز گذار میان دو قلمرو تکتونیکی متفاوت گستره شمال باختر ایران، بررسی تحولات ساختاری آن میتواند به بازسازی بهتر تاریخچه ژئودینامیکی شمال باختر ایران کمک کند. از اینرو، در این پژوهش سعی شده است با کمک تصویرهای ماهوارهای، بررسی و برداشت میدانی ساختارها (از جمله هندسه چینخوردگیها و دادههای هندسی و جنبشی گسلهها) و وارونسازی دادههای جنبشی گسلهها، تحولات ساختاری دیرین حوضه ماهنشان- میانه بررسی شود. بررسی الگوی سطحی و اندازه-گیریهای ساختاری نشان میدهد چینهای اصلی گستره که ناشی از دگرریختی اواخر میوسن میانی هستند، با گامه جوانتری از چینها که راستای محوری شمالخاور- جنوبباختر دارند، فرا نهاده شدهاند. بر پایه شواهد ساختاری و چینهشناسی، گامه دوم در بازه زمانی پلیوسن تا کواترنری رخ داده است. وارونسازی دادههای جنبشی گسلهها گویای وجود یک رژیم فشارشی دیرین، اواخر پلیوسن- کواترنری، با راستای محور بیشینه فشارش افقی شمالباختر- جنوبخاور در حوضه رسوبی ماهنشان- میانه است که پیش از سامانه تنش امروزی، با راستای شمال -خاور- جنوب باختر، بر این گستره چیره بوده است. چنین راستای فشارشی میتواند مسبب تشکیل چینهای گامه دوم در گستره حوضه رسوبی ماهنشان- میانه باشد.
Authemayou, C., Chardon, D., Bellier, O., Malekzadeh, Z., Shabanian, E. and Abbasi, M.R. (2006) Late Cenozoic partitioning of oblique plate convergence in the Zagros fold-and-thrust belt (Iran). Tectonics, 25, TC3002.
Navabpour, P., Angelier, J., and Barrier, E. (2007) Cenozoic post-collisional brittle tectonic history and stress reorientation in the High Zagros Belt (Iran, Fars Province). Tectonophysics, 432, 101â131.
Navabpour, P., Angelier, J., and Barrier, E. (2011) Brittle tectonic reconstruction of palaeo-extension inherited from mesozoic rifting in west Zagros (Kermanshah, Iran). Journal of Geological Society, London, 168, 979-994.
Zanchi, A., Berra, F., Mattei, M., Ghassemi, M.R., and Sabouri, J. (2006) Inversion tectonics in central Alborz, Iran. Journal of Structural Geology, 28, 2023-2037.
Shabanian, E., Bellier, O., Abbassi, M., Siame, L., and Farbod, F. (2010) Plio-Quaternary stress states in NE Iran: Kopeh Dagh and Allah Dagh-Binalud mountain ranges. Tectonophysics, 480, 280â304.
Javidfakhr, B., Bellier, O., Shabanian, E., Siame, L., Leanni, L., Bourlès, D., and Ahmadian, S. (2011) Fault kinematics and active tectonics at the southeastern boundary of the eastern Alborz (Abr and Khij fault zones): geodynamic implications for NNE Iran. Journal of Geodynamics, 52(3â4), 290â303.
Regard, V., Bellier, O., Thomas, J.-C., Abbassi, M.R., Mercier, J., Shabanian, E., Feghhi, K., and Soleymani, S. (2004) Accommodation of Arabia-Eurasia convergence in the Zagros-Makran transfer zone, SE Iran: A transition between collision and subduction through a young deforming system. Tectonics, 23, TC4007.
Dolati, A. and Burg, J.P. (2013) âPreliminary fault analysis and paleostress evolution in the Makran Fold-and-Thrust Belt in Iranâ. In: Lithosphere Dynamics and Sedimentary Basins: The Arabian Plate and Analogues, Part of the series Frontiers in Earth Sciences, 261-277.
Kargaranbafghi, F., Franz Neubauer, F., and Genser, J. (2011) Cenozoic kinematic evolution of southwestern Central Iran: Strain partitioning and accommodation of ArabiaâEurasia convergence. Tectonophysics, 502, 221-243.
Salmanlu, A. (2015) Late Cenozoic Change in the Stress State of the Zanjan Region; Implications for the Geodynamics of NW Iran. B.Sc. Thesis, Bu-Ali Sina University, Hamedan, Iran, 193 p (in Persian).
Aflaki, M., Shabanian, E., Dvoodi, Z. (2016) Quaternary stress state in Mahneshan-Mianeh Cenozoic sedimentary basin (NW Iran), deduced from fault kinematics data. 34th Geosciences congress, Geological Society of Iran, Tehran (in Persian).
Ghods, A., Shabanian, E., Bergman, E., Faridi, M., Donner, S., Mortezanejad, G., and Aziz-Zanjani, A. (2015) The VarzaghanâAhar, Iran, Earthquake Doublet (Mw 6.4, 6.2): implications for the F., Guliev, I., Stepanyan, R., Nadariya, M., Hahubia, G., Mahmoud, S., Sakr, K., ArRajehi, A., Paradissis, D., Al-Aydrus, A., Prilepin, M., Guseva, T., Evren, E., Dmitrotsa, A., Filikov S.V., Gomez, F., Al-Ghazzi, R. and Karam, G. (2006) GPS constraints on continental deformation in the Africa-Arabia-Eurasia continental collision zone and implications for the dynamics of plate interactions. Journal of Geophysical Research, 111, B05411.
Regard, V., Hatzfeld, D., Molinaro, M., Aubourg, C., Bayer, R., Bellier, O., Yamini-Fard, F., Peyret, M., and Abbasi, M. (2009) The transition between Makran subduction and the Zagros collision: recent advances in its structure and active deformation. Geological Society, London, Special Publications, 330, 43-64.
Vernant, P. and Chery, J. (2006) Low fault friction in Iran implies localized deformation for the ArabiaâEurasia collision zone. Earth and Planetary Science Letters, 246, 197â206.
Djamour, Y., Vernant, P., Nankali, H.R., and Tavakoli, F. (2011) NW Iran-eastern Turkey present-day Kinematics: Results from the Iranian permanent GPS network. Earth and Planetary Science Letters, 307, 27-34.
Mousavi, Z., Walpersdorf, A., Walkerc, R.T., Tavakoli, F., Pathier, E., Nankali, H., Nilfouroushan, F., and Djamour, Y. (2013) Global Positioning System constraints on the active tectonics of NE Iran and the South Caspian region. Earth and Planetary Science Letters, 287-298.
Zarifi, Z., Nilforoushan, F., and Raeesi, M. (2014) Crustal Stress Map of Iran: Insight from Seismic and Geodetic Computations. Pure and Applied Geophysics, 171, 1219-1236.
Masson, F., Lehujeur, M., Ziegler, Y., and Doubre, C. (2014) Strain rate tensor in Iran from a new GPS velocity field. Geophysical Journal International, doi: 10.1093/gji/ggt509.
Allen, M.B., Ghassemi, M.R., Shahrabi, M., and Qorashi, M. (2003) Accommodation of late
geodynamics of northwest Iran. Geophysical Journal International, 203, 522-540.
Azad, S.S., Ritz, J.F., and Abbassi, M.R. (2011) Left-lateral active deformation along the MoshaâNorth Tehran fault system (Iran): Morphotectonics and paleoseismological investigations. Tectonophysics, 497(1), 1-14.
Azad, S.S., Philip, H., Dominguez, S., Hessami, K., Shahpasandzadeh, M., Foroutan, M., Tabassi, H., and Lamothe, M. (2015) Paleoseismological and morphological evidence of slip rate variations along the North Tabriz fault (NW Iran). Tectonophysics, 640, 20-38.
Nilforoushan, F., Masson, F., Vernant, P., Vigny, C., Martinod, J., Abbassi, M., Nankali, H., Hatzfeld, D., Bayer, R., Tavakoli, F., Ashtiani, A., Doerflinger, E., Daignieres, M., Collard, P., and Chery, J. (2003) GPS network monitors the Arabia-Eurasia collision deformation in Iran. Journal of Geodesy, 77, 411â422.
Vernant, P., Nilforoushan, F., Hatzfeld, D., Abbassi, M.R., Vigny, C., Masson, F., Nankali, H., Martinod, J., Ashtiani, A., Bayer, R., Tavakoli, F., and Ch´ery, J. (2004) Present-day crustal deformation and plate kinematics in the Middle East constrained by GPS measurements in Iran and northern Oman. Geophys. J. Int., 157, 381â398.
Masson, F., Djamour, Y., Van Gorp, S., Chery, J., Tatar, M., Tavakoli, F., Nankali, H., and Vernant, P. (2006) Extension in NW Iran driven by the motion of the South Caspian Basin. Earth and Planetary Science Letters, 252, 180â188.
Regard, V., Bellier, O., Thomas, J.-C., Bourlès, D., Bonnet, S., Abbassi, M.R., Braucher, R., Mercier, J., Shabanian, E., Soleymani, Sh., and Feghhi, Kh. (2005) Cumulative right-lateral fault slip rate across the ZagrosâMakran transfer zone: role of the MinabâZendan fault system in accommodating ArabiaâEurasia convergence in southeast Iran. Geophys. J. Int., 162, 177â203.
Reilinger, R., McClusky,S., Vernant, P., Lawrence, S., Ergintav, S., Cakmak, R., Ozener, H., Kadirov,
Cenozoic oblique shortening in the Alborz range, northern Iran. Journal of Structural Geology, 25, 659-672.
Ritz, J., Nazari, H., Ghassemi, A., Salamati, R., Shafei, A., Solaymani, S., and Vernant, P. (2006) Active transtension inside central Alborz: A new insight into northern Iranâsouthern Caspian geodynamics. Geology, 34, 477â480.
Westaway, R. (1994) Present-day kinematics of the Middle East and eastern Mediterranean. J. Geophys. Res., 99(B6), 12071â12090.
Afshar, F.A. (1965) Geology of Mianeh district of Northwestern Iran. Bull. Min. Res. Expl. Inst. Turkey, 64, 57-72.
Emami, M.H. (1990) Geological map of Mianeh quadrangle. Geological Survey of Iran, Tehran, scale 1:100,000.
Lotfi, M. (2001) Geological map of Mahneshan quadrangle. Geological Survey of Iran, Tehran, scale 1:100,000.
Ballato, P., Cifelli, F., Heidarzadeh, G., Ghassemi, M.R., Wickert, A.D., Hassanzadeh, J., Dupont-Nivet, G., Balling, P., Sudo, M., Zeilinger, G., Schmitt, A.K., Mattei, M., and Strecker, M.R. (2017) Tectono-sedimentary evolution of the northern Iranian Plateau: insights from middleâlate Miocene foreland-basin deposits. Basin Res., 29(4), 417â446, doi:10.1111/bre.12180.
Baghernejhad, M., Ghassemi, M.R., and Oveisi, B. (2014) Detachment folding in Mianeh-Mahneshan area: Interaction between sedimentation in the Upper Red Formation basin and shortening. Geosciences, 24(95), 169-180.
Carey-Gailhardis, E. and Mercier, J.L. (1987) A numerical method for determining the state of stress using focal mechanisms of earthquake populations: Application to Tibetan teleseisms and icroseismicity of southern Peru. Earth Planet. Sci. Lett., 82(1), 165-179.
Ritz, J.F. and Taboada, A. (1993) Revolution stress ellipsoids in brittle tectonics resulting from an uncritical use of inverse methods. Bull. Soc. Geol. France, 164, 519-531.
Bellier, O. and Zoback, M.L. (1995) Recent state of stress change in the Walker Lane zone,western Basin and Range province, United States. Tectonics, 14, 564â593.
Abbasi, M.R. and Shabanian, E. (1999) Evolution of the stress field in Tehran region during the quaternary. Proceeding of Third International Conference on Seismology and Earthquake Engineering (SEE-3), 67-84.
Abbasi, M.R. and Shabanian, E. (2005) Determination of stress state and direction by inversion of fault-slip data in the southern flank of Central Alborz. Geosciences, 55, 2-18 (in Persian).
Abbassi, M.R., Mokhtari, H. (2016) Investigation of Morphological Features and Faulting Mechanisms of NW-Striking Faults Affecting Alluvial Deposits in Tehranâs Piedmont. Bulletin of Earthquake Science and Engineering, 3(1), 1-15.