Document Type : Original Research Paper
Author
Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran
Abstract
Bajgan metamorphic complex is located at the southeastern termination of the Sanandaj-Sirjan zone in north of Makran. The metamorphic rocks, having igneous and sedimentary origins, are in tectonic contact with ophiolite assemblages and colored mélange. The rocks can be divided in four units based on lithological characteristics. These units are covered by Pliocene and Quaternary sediments. Structural study indicates the presence of three syn-metamorphic stages of deformation in ductile condition. The main structures elements are different generation of folds, foliation and lineation, each of them has been generated during a specific stage and superimposed on each other. The structural elements in this complex have emerged during subduction, ophiolite obduction and exhumation, respectively.
Keywords
Main Subjects
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Sarkarinejad, K., 1999. Tectonic finite strain analysis using: Ghouri deformed conglomerate, Neyriz area, Southwestern Iran. Iranian Journal of Science and Tecnology. 23, 352–363.
Sarkarinejad, K., and Azizi, A., 2008. Slip partitioning and inclined dextral transpressio along the Zagros Thrust System, Iran. Journal of Structural Geolgy. 30, 116–136.
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Sheikholeslami, R., Bellon, H., Emami, H., Sabzehei, M., and Pique, A., 2003. Nouvelles données structurales et datations 40K/40Ar surles roches métamorphiques de la region de Neyriz (zone de Sanandaj-Sirjan, Iran méridional). Leur intérêt dans le carde du domaine néo-téthysien du Moyen-Orient. C. R. Geosci. 335, 981–991.
Burg, J.-P., 2018. Geology of the onshore Makran accretionary wedge: Synthesis and tectonic interpretation. Earth Sci. Rev. 185, 1210-1231.
Davoudian, A. R., Genser, J., Dachs, E., and Shabanian, N., 2008. Petrology of eclogites from north of Shahrekord, Sanandaj-Sirjan Zone, Iran. Mineralogy and Petrology 92, 393– 413.
Delavari, M., Dolati, A., Marroni, M., Pandolfi, L., and Saccani E., 2016. Association of MORB and SSZ ophiolites along the shear zone between Coloured Mélange and Bajgan Complexes (North Makran, Iran): Evidence from the Sorkhband area. Ofioliti, 41, 21-34.
Dorani, M., Arvin, M., Oberhänsli, R., and Dargahi, S., 2017. P-T evolution of metapelites from the Bajgan complex in the Makran accretionary prism, south eastern Iran. Geochem. 77, 459–475.
Hassanzadeh, J., and Wernick, B.P., 2016. The Neotethyan Sanandaj-Sirjan zone of Iran as an archetype for passive margin-arc transitions. Tectonics 35, 586–621.
Hunziker, D., 2014. Magmatic and Metamorphic History of the North Makran Ophiolites and Blueschists (SE Iran): Influence of Fe3+/Fe2+ Ratios in Blueschist Facies Minerals on Geothermobarometric Calculations. ETH Zurich, Switzerland, Zürich (ETH-Zürich 364 pp).
Hunziker, D., Burg, J.P., Bouilhol, P., and Quadt, A., 2015. Jurassic rifting at the EurasianTethys margin: geochemical and geochronological constraints from granitoids of North Makran, SE Iran. Tectonics 34 (3), 571–593.
Hushmand Zadeh, A., and Berberian, M., 1972. A brief note on early kimmerian orogeny and high grade metamorphism in the Sanandaj-Sirjan belt, Iran. Ministry of Economy, Geological Survey of Iran.
Hushmand Zadeh, A., 1977. Ophiolites of south Iran and their problems: unpublished report field, Geological and Mineral Survey of Iran.
Keary, P., Klepeis, K.A., and Vine, F.J., 2009. Global Tectonic, third ed. Wiley-Blackwell,482 p.
McCall, G.J.H., 1985. Explanatory Text of the Minab Quadrangle Map: 1:250,000, No. J13. Geological Survey of Iran, Tehran, 530 p.
McCall, G.J.H., 1997. The geotectonic history of the Makran and adjacent areas of southern Iran.J. Asian Earth Sci. 15, 517-531.
McCall, G.J.H., and Kidd, R.G.W., 1982. The Makran southeastern Iran: the anatomy of a convergent margin active from Cretaceous to present. In: Leggett, J.K. (Ed.), Trench-forearc geology: sedimentation and tectonics of modern and ancient plate margins, Geological Society of London Special Publications vol. 10, pp. 387-397.
McCall, G.J.H., 2002. A summary of the geology of the Iranian Makran. Geological Society, London, Special Publications, v. 195, p. 147-204
Miyashiro, A., 1961. Evolution of metamorphic belts. Journal of Petrology 2, 277–311.
Oxburgh, E.R., and Turcotte, D.I., 1971. Origin of paired metamorphic belts and crustal dilation in Island arc regions’’. J. Geophys. Res. 76, 1315–1327.
Pandolfi, L., Barbero, E., Marroni, M., Delavari, M., Dolatid, A., Di Rosa, M., Frassi, C., Langone, A., Farina, F., MacDonald, C. S., and Saccani, E., 2021. The Bajgan Complex revealed as a Cretaceous ophiolite-bearing subduction complex: A key to unravel the geodynamics of Makran (southeast Iran). Journal of Asian Earth Sciences, 222,104965.
Sabzehei, M., 1974. Les mélanges ophiolitiques de la région d’Esfandageh (Iran méridional). Etude pétrologique et structurale; interprétation dans le cadre Iranien, Ph.D. thesis, 306 pp., Université de Grenoble, Grenoble, France.
Sarkarinejad, K., 1999. Tectonic finite strain analysis using: Ghouri deformed conglomerate, Neyriz area, Southwestern Iran. Iranian Journal of Science and Tecnology. 23, 352–363.
Sarkarinejad, K., and Azizi, A., 2008. Slip partitioning and inclined dextral transpressio along the Zagros Thrust System, Iran. Journal of Structural Geolgy. 30, 116–136.
Sheikholeslami, M.R., 2002. Evolution structurale et métamorphique de la marge sud de la microplaque de l’Iran central: les complexes métamorphiques de la région de Neyriz (zone de Sanandaj-Sirjan), Thèse, université de Brest, 194 p.
Sheikholeslami, R., Bellon, H., Emami, H., Sabzehei, M., and Pique, A., 2003. Nouvelles données structurales et datations 40K/40Ar surles roches métamorphiques de la region de Neyriz (zone de Sanandaj-Sirjan, Iran méridional). Leur intérêt dans le carde du domaine néo-téthysien du Moyen-Orient. C. R. Geosci. 335, 981–991.
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