Calc-alkaline magmatism associated with salt diapirs in the Shurab and Garmsar back-arc areas (Central Basin, Iran): magma genesis and tectonic implications

  Medium- and high-K calc-alkaline magmatism of the Shurab (southeast Qom city) and Garmsar (northwest Garmsar city) areas occurred within the Lower Red Formation in the Central Basin behind the Urumieh-Dokthar Magmatic Arc. In terms of whole-rock geochemical analyses and in agreement with the petrographic features, all representative samples of the Shurab area are classified into three groups: group 1 with mainly intergranular texture comprises basalt/trachybasalt, while groups 2 and 3 with trachytic and porphyritic textures, respectively, have basaltic trachyandesite composition. The overall major constituents are plagioclase with composition in the range from An49Ab23 to An75Ab47, clinopyroxene with composition in the range Wo43-45En39-45Fs9-15, and olivine with composition in the range from Fo58Fa31 to Fo67Fa40. Minor minerals consist of opaque minerals and K-feldspar in the range Or41-65Ab33-50An0.69-8. The characteristic accessories are apatite and sphene. In the Garmsar area, rocks are seen as subvolcanic with mafic (basalt) and intermediate (trachybasalt/basaltic trachyandesite) compositions. The Garmsar area rocks represent intergranular, granular, ophitic, and subophitic textures. In these rocks, major mineral phases are plagioclase and clinopyroxene. The minor constituents are olivine, opaque minerals, amphibole, biotite, and quartz. Apatite is the most important accessory mineral. The rocks of both areas display REE patterns characterized by LREE-enriched and HREE-depleted segments typical of arc lavas. Primitive mantle-normalized trace element patterns for samples of both areas exhibit high ratios of strongly incompatible elements with similar bulk partition coefficients (e.g., Th/ Ta and Th/Ce), enrichment in large-ion lithophile elements (LILEs: Cs, Ba, Rb, Th) relative to the high field-strength elements (HFSEs: Ti, Hf, Zr, and REEs), and troughs for Nb, Ta, Ti, and Zr and peaks for Cs, Th, K, and Sr, all of which are indicators for subductionrelated magmatism. Subduction of the Neo-Tethys beneath the Eurasian margin led to upper mantle deformation and metasomatism. Once the Arabian plate collided with the Eurasian margin, subduction ended through a slab breakoff process, and thermal flux of asthenospheric origin uprising through the slab tear induced the thermal erosion of the mantle metasomatized during the previous subduction event and triggered its partial melting. Also, the late Eocene-early Oligocene collision of Eurasian with Arabian plates led to the subsidence and formation of faults and extensions in the Central Basin (i.e. the Shurab and Garmsar areas) such that eruption of medium- and high-K metasomatic magmatism along these faults and extensions caused postcollision volcanism in the Central Basin.

___

  • Abaie I, Ansari JJ, Badakhshan A, Jaafari A (1964). History and development of the Alborz and Sarajeh fields of Central Iran. In: World Petroleum Congress Proceedings, pp. 697-713.
  • Allen MB, Kheirkhah M, Emami MH, Jones SJ (2011). Right-lateral shear across Iran and kinematic change in the Arabia-Eurasia collision zone. Geophys J Int 184: 555-574.
  • Amini B, Emami MH (1996). Geology Map of Aran, Scale 1:100,000. Tehran, Iran: Geological Society of Iran.
  • Amini B, Rashid H (2004). Geology Map of Garmsar, Scale 1:100,000. Tehran, Iran: Geological Society of Iran.
  • Berberian M, King GCP (1981). Towards a palaeogeography and tectonic evolution of Iran. Can J Earth Sci 18: 210-265.
  • Best MG (2003). Igneous and Metamorphic Petrology. Oxford, UK: Blackwell.
  • Bina MMI, Bucur M, Prevot Y, Meyerfeld L, Daly Cantagrel JM, Mergoil J (1986). Palaeomagnetism, petrology and geochronology of Tertiary magmatic and sedimentary units from Iran. Tectonophysics 121: 303-329.
  • Bird P (1979). Continental delamination and the Colorado Plateau. J Geophys Res 84: 7561-7571.
  • Bouzari S, Konon A, Koprianiuk M, Julapour AA (2013). Thin- skinned tectonics in the Central Basin of the Iranian Plateau in the Semnan area, Central Iran. J Asian Earth Sci 2: 269-281.
  • Chung SL, Chu, MF, Zhang YQ, Xie YW, Lo CH, Lee TY, Lan CY, Li XH, Zhang Q, Wang YZ (2005). Tibetan tectonic evolution inferred from spatial and temporal variations in postcollisional magmatism. Earth-Sci Rev 68: 173-196.
  • Conticelli S, Guarnieri L, Farinelli A, Mattei M, Avanzinelli R, Bianchini G, Boari E, Tommasini, S, Tiepolo M, Prelevic D et al. (2009). Trace elements and Sr-Nd-Pb isotopes of K-rich, shoshonitic, and calc-alkaline magmatism of the Western Mediterranean Region: genesis of ultrapotassic to calcalkaline magmatic associations in a post-collisional geodynamic setting. Lithos 107: 68-92.
  • Dacheng J, Ruizhong H, Yan L, Guiqing X, Xuelin Q (2004). Characteristics of the mantle source region of sodium lamprophyres and petrogenetic tectonic setting in northeastern Hunan, China. Sci China Ser D 47: 559-569.
  • Davies JH, von Blanckenburg F (1995). Slab breakoff: a model of lithosphere detachment and its test in the magmatism and deformation of collisional orogens. Earth Planet Sc Lett 129: 85-102.
  • Deer WA, Howie RA, Zussma J (1991). An Introduction to Rock Forming Minerals. London, UK: Longman.
  • Didier J (1991). The main types of enclaves in the Hercynian granitoids of the Massif Central, France. In: Didier J, Barbarin B, editors. Enclaves and Granite Petrology. Developments in Petrology. Amsterdam, the Netherlands: Elsevier, pp. 47-61.
  • D’orazio M, Innocenti F, Manetti P, Haller MJ (2004). Cenozoic back arc magmatism of the southern extra-Andean Patagonia (44° 30’–52° S): a review of geochemical data and geodynamic interpretations. Revista de la Asociación Geológica Argentina 59: 525-538.
  • Duggen S, Hoernle K, Van den Bogaard P, Garbe-Schonberg D (2005). Post-collisional transition from subduction- to intraplate-type magmatism in the westernmost Mediterranean: evidence for continental edge delamination of subcontinental lithosphere. J Petrol 46: 1155-1201.
  • Elliott T, Plank T, Zindler A, Whit W, Bourdon B (1997). Element transport from slab to volcanic front at the Mariana arc. J Geophys Res-Earth 102: 14991-15019.
  • Furrer MA, Sonder PA (1955). The Oligo-Miocene marine formation in the Qum region (Central Iran). In: Proceedings of the Fourth World Petroleum Congress, Section 1/A/5, Rome, Italy, pp. 270-277.
  • Gansser A (1955). New aspects of the geology of Central Iran. In: Proceedings of the Fourth World Petroleum Congress, Section 1/A/5, Rome, Italy, pp. 286-305.
  • Garrido CJ, Bodinier JL, Alard O (2000). Incompatible trace element partitioning and residence in anhydrous spinel peridotite and websterites from the Ronda orogenic peridotite. Earth Planet Sc Lett 181: 341-358.
  • Gill JB (1981). Orogenic Andesites and Plate Tectonics. Berlin, Germany: Springer.
  • Harker A (1909). The Natural History of Igneous Rocks. London, UK: Methuen, Methuen and Co.
  • Hassanzadeh J, Ghazi AV, Axen G, Guset B (2002). Oligo-Miocene mafic-alkaline magmatism in north and northwest of Iran: evidence for the separation of the Alborz from the Urumieh- Dokhtar magmatic arc. Abstracts with Programs - Geological Society of America 34: 331.
  • Hawkesworth CJ, Gallagher K, Hergt JM, McDermott F (1993). Mantle and slab contributions in arc magmas. Annu Rev Earth Planet Sc Lett 21: 175-204.
  • Huber H (1952). Geological Report on the Upper Qara-Chai area between Saveh and Hamadan. Tehran, Iran: Iranian Oil Company Geological Report.
  • Hui H, Peslier AH, Lapen TJ, Shafer JT, Brandon AD, Irving AJ (2011). Petrogenesis of basaltic shergottite Northwest Africa 5298: closed-system crystallization of an oxidized mafic melts. Meteorit Planet Sci 46: 1313-1328.
  • Jahangiri A (2007). Post-collisional Miocene adakitic volcanism in NW Iran: geochemical and geodynamic implications. J Asian Earth Sci 30: 433-444.
  • Jung C (2003). Geochemische und Isotopen-geoschemische untersuchungen a tertiaeren Vulkaiten der Hocheifel ein Beitrag zur Identifizierung der mantelquellen Von rift- bezogenen Vulkaniten. Doctorate thesis, Universität Marburg, Marburg, Germany (in German).
  • Karmalker NRS, Griffin WL, O’Reilly SY (2005). Alkaline magmatism from Kutch, NW India: implications for plume-lithosphere interaction. Lithos 81: 101-119.
  • Kay SM, Gorring ML, Ramos VA (2004). Magmatic sources, setting and causes of Eocene to Recent Patagonian plateau magmatism (36 ° to 52 ° latitude). Revista de la Asociación Geológica Argentina 59: 556-568.
  • Kelemen PB, Hangh JK, Greene AR (2003). One view of the geochemistry of subduction-related magmatic arcs, with an emphasis on primitive andesite and lower crust. In: Rudnick R, editors. Treatise on Geochemistry. Amsterdam, the Netherlands: Elsevier, pp. 593-659.
  • Kretz R (1983). Symbols for rock-forming minerals. Am Mineral 68: 277-279.
  • Lafleche MR, Camir G, Jenner GA (1998). Geochemistry of post- Acadian, Carboniferous continental intra-plate basalts from the Maritimes Basin, Magdalen Islands, Quebec, Canada. Chem Geol 148: 115-136.
  • Le Maitre R, editor (1989). A Classification of Igneous Rocks and Glossary of Terms. Oxford, UK: Blackwell.
  • Litasov Y, Hasenaka T, Litasov K, Yarmolyuk V, Sugorakova A, Lebedev V, Sasaki M, Taniguchi H (2001). Petrologic characteristics of Cenozoic alkaline basalts from the Azas Plateau, Northeast Tuva (Russia). Center for Northeast Asian Studies - Tohoku University 3: 201-226.
  • Mancilla FL, Booth-Rea G, Pérez-Peña JV, Morales J, Azañon JM, Martin R, Giaconia F (2015). Slab rupture and delamination under the Betics and Rif constrained from receiver functions. Tectonophysics 663: 225-237.
  • Martin H (1999). Adakitic magmas, modern analogues of Archaean granitoid. Lithos 46: 411-429.
  • Matthias W, Stracke A (2006). Trace element composition of mantle end-members: Implications for recycling of oceanic and upper and lower continental crust. Geochem Geophy Geosy 7: 1-30.
  • McCulloch MT, Gamble AJ (1991). Geochemical and geodynamical constraints on subduction zone magmatism. Earth Planet Sc Lett 102: 358-374.
  • Morimoto N (1989). Nomenclature of pyroxenes. Can Mineral 27: 143156.
  • Morley CK, Kongwung B, Julapour AA, Abdolghafourian M, Hajian M, Waples D, Warren J, Otterdoom H, Srisuriyon K, Kazemi H (2009). Structural development of a major late Cenozoic basin and transpressional belt in Central Iran: the Central Basin in the Qom-Saveh area. Geosphere 5: 1-38.
  • Muller D, Rock NMS, Groves DI (1992). Geochemical discrimination between shoshonite and potassic volcanic rocks in different tectonic settings: a pilot study. Miner Petrol 46: 259-289.
  • Pearce JA (1982). Trace element characteristics of lavas from destructive plate boundaries. In: Thorpe RS, editor. Andesites: Orogenic Andesites and Related Rocks. New York, NY, USA: Wiley and Sons, pp. 525-548.
  • Pearce JA (1983). The role of sub-continental lithosphere in magma genesis at destructive plate margins. In: Hawkesworth CJ, Norris MJ, editors. Continental Basalts and Mantle Xenoliths. Nantwich, UK: Shiva, pp. 230-249.
  • Pearce JA, Peate DW (1995). Tectonic implications of the composition of volcanic arc magmas. Annu Rev Earth Planet Sc 23: 251-285.
  • Rajesh KS, Rao NVC (2007). Petrology, geochemistry and tectonic significance of Palaeoproterozoic alkaline lamprophyres from the Jungel Valley, Mahakoshal supracrustal belt, Central India. Miner Petrol 89: 189-215.
  • Ramos VA, Kay SM (2006). Overview of the tectonic evolution of the southern Central Andes of Mendoza and Neuquén (35°– 39°S latitude). In: Kay SM, Ramos VA, editors. Evolution of an Andean Margin: A Tectonic and Magmatic View from the Andes to the Neuquén Basin (35°–39°S Latitude). Boulder, CO, USA: Geological Society of America, pp. 1-17.
  • Rogers NW, Hawkesworth CJ, Parker RJ, Marsh JR (1985). The geochemistry of potassic lavas from Vulsini, central Italy and implications for mantle enrichment processes beneath the Roman region. Contrib Mineral Petr 90: 244-257.
  • Rollinson HR (1993). Using Geochemical Data: Evaluation, Presentation and Interpretation. New York, NY, USA: John Wiley and Sons.
  • Sarizan R (2014). Stratigraphical position, petrology and geochemistry of igneous intrusion exist in Lower Red Formation (North of Garmsar) MSc, University of Shahrood, Shahrood, Iran.
  • Saunders A, Tarrney DJ (1984). Geochemical characteristics of basaltic volcanism within back-arc basins. Geol Soc Spec Publ 16: 59-76.
  • Skewes MA, Stern CR (1979). Petrology and geochemistry of alkali basalts and ultramafic inclusions from the Pali-Aike volcanic field in southern Chile and the origin of the Patagonian plateau lavas. J Volcanol Geoth Res 6: 3-25.
  • Stern CR (2004). Active Andean volcanism: its geologic and tectonic setting. Rev Geol de Chile 31: 161-206.
  • Stocklin J (1968). Structural history and tectonics of Iran: a review. AAPG Bull 52: 1229-1258.
  • Sun S, McDonough W (1989). Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In: Saunders D, Norry MJ, editors. Magmatism in the Ocean Basins. London, UK: Geological Society of London, pp. 313-345.
  • Temizel İ, Arsalan M, Ruffet G, Peucat JJ (2012). Petrochemistry, geochronology and Sr-Nd isotopic systematics of the Tertiary collisional and post-collisional volcanic rocks from the Ulubey (Ordu) area, eastern Pontide, NE Turkey: implications for extension-related origin and mantle source characteristics. Lithos 128: 126-147.
  • Tarney J, Saunders AD, Mattey DP, Wood DA, Marsh NG, Roberts D (1981). Geochemical aspects of back-arc spreading in the scotia sea and western pacific (and discussion). Philos T R Soc S-A 300: 263-285.
  • Thompson RN, Morrison MA, Hendry GL, Parry SJ, Simpson PR, Hutchison RM, O’Hare J (1984). An assessment of the relative roles of crust and mantle in magma genesis: an elemental approach [and discussion]. Philos T R Soc S-A 310: 549-590.
  • Vincent I, Allen MB, Ismailzadeh AD, Flecker R, Foland KA, Simmons D (2005). Insights from the Talysh of Azerbaijan into the Paleogene evolution of the south Caspian region. Geol Soc Am Bull 117: 1513-1533.
  • Wang Q, Wyman DA, Xu JF, Wan Y, Li CH, Zi F, Jiang Z, Qiu H, Chu Zh, Zhao ZH et al. (2008). Triassic Nb-enriched basalts, magnesian andesites, and adakites of the Qiangtang terrane (Central Tibet): evidence for metasomatism by slab-derived melts in the mantle wedge. Contrib Mineral Petr 155: 473-490.
  • Winchester JA, Floyd P (1977). Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chem Geol 20: 325-343.
  • Workman RK, Hart SR (2005). Major and trace element composition of the depleted MORB mantle (DMM). Earth Planet Sc Lett 231: 53-72.
  • Zanetti A, Mazzucchelli M, Vannuci R (1999). The Finero phlogopite-peridotite massif: an example of subduction- related metasomatism. Contrib Mineral Petr 134: 107-122.
  • Zhang Y, Liu J, Guo Z (2010). Permian basaltic rocks in the Tarim basin, NW China: implications for plume-lithosphere interaction. Gondwana Res 18: 596-610.
  • Zorpi MJ, Coulon C, Orisini JB, Concirta C (1989). Magma mingling, zoning and emplacement in calk-alkaline granitoid plutons. Tectonophysics 157: 315-326.