Petrography and geochemistry of volcanic rocks of Molaahmad pass (East Isfahan, Centeral Iran)

Paper Details

Research Paper 01/06/2015
Views (214) Download (8)

Petrography and geochemistry of volcanic rocks of Molaahmad pass (East Isfahan, Centeral Iran)

Zahra Nasr Esfahani, M. H. Emami, S. J. Sheikhzakariaee, S. H. Tabatabaei
J. Bio. Env. Sci.6( 6), 438-447, June 2015.
Certificate: JBES 2015 [Generate Certificate]


The studied area is located in east of Isfahan province. This area is the part of Uromiah- Dokhtar zone in Central Iran. Eocene volcanic rocks Mehrabad region (Molaahmad pass) consists mainly of intermediate-felsiclavasandesite to Dacite and pyroclastic rocks of the tuff. The volcanic rocks are composed of plagioclase, amphibole, quartz , opaque andglass. Most offerromagnesian minerals alterated to chlorite , cacite and epidote. On the base of geochemical studies, volcanic rocks are ranging from sub-alkalineandthey are a medium to high K calc-alkaline suite. In the Trace elements spider diagram, these similar to upper crust. They are generated partial melting of crustal protoliths. Enrichment in LILE and depletion of HFSE in the studied rocks as well as various petrologic diagrams point to magmatism in arc of an active continental margin.


Aftabi A, Atapour H. 2000. Regional aspects of shoshonitic volcanism in Iran. Episodes 23(2), 119-125.

Agard P, Omrani J, Jolivet L, Whitechurch H, Vrielynck B, Spakman W, Monie P, Meyer B, and Wortel R. 2011. Zagros orogeny: a subduction-dominated process. In: Geodynamic Evolution of the Zagros (Eds. Lacombe, O., Grasemann, B. and Simpson, G.). Geological Magazine 692-725.

Allen M, Jackson J, Walker R. 2004. Late Cenozoic reorganizatoin of the Arabia-Eurasia collision and comparison of short-term and long-term deformation rates. Tectonics 23, 1-16.

Amidi SM, Emami MH, Michel R. 1984. Alkaline character of Eocene volcanism in the middle part of Central Iran and its geodynamic situation. Geologische Rundschau 73, 917-932.

Amini B, Amini Chehragh MR. 2003. 1:100000 Geological map of Kajan. Geological survey and mineral explorations of Iran.

Cox KG, Bell JD, Pankhurst RJ. 1979. The interpretation of igneous rocks. George, Allen and Unwin 45p.

Dewey DE, Hempton MR, Kidd WSF, Saroglu F, Sengo AWC. 1986. Shortening of continental lithosphere: The neotectonics of Eastern Anatolia- a young collision zone, In. coward, M.P., Ries, A.C., (Eds), collision zone Tectonics, Geological society of London Special Publication 19, 3-36.

Dewey JF, Pitman WC, Ryan WB, Bonnin J. 1973. Plate tectonics and the evolution of the Alpine system. Geol Soc Am Bull 84,3137–3180

Dilek Y, Imamverdiyev N, Altunkaynak S. 2010. Geochemistry and tectonics of Cenozoic volcanism in the Lesser Caucasus (Azerbaijan) and the part-Arabian region: collision- induced mantle dynamics and its magmatic fingerprint-International Geology Review 52, 536-578.

Dilek Y, Sanduol E. 2009. Seismic structure, crustal architecture and tectonic evolution of the Anatolian-African plate boundary and the Cenozoic organic belts in the eastern Mediterranean region. Geological society ofLondon special publication 327, 127-160

Dilek Y, Whitney DL. 2000. Cenozoic crustal evolution in central Anatolia: Extension, magmatism and landscape development. Proceedings of the Third International Conference on the Geology of the Eastern Mediterranean, Geological Survey Department, September 1998, Nicosia-Cyprus 183– 192.

Dimitrijevic MD. 1973. Geology of Kerman region. Geological Survey of Iran, Tehran.

Dunphy JM, Ludden JN. 1998. Petrological and geochemical characteristics of a Paleoproterozoic magmatic arc (Narsajuaq terrane, Ungava, Canada) and compositions to Superior Province granitoids. Precambrian Research 91, 109-152.

Emami MH. 1981. Geologie de la region de Qom-Aran(Iran).Contribution a letude dynamique et geochimique du volcanisme tertiaire de Iran central. These doctrat d Etat, Grenoble, 489p.

Emami MH. 2000. Magmatism in Iran. Geological Survey of Iran, Tehran.

Farahoudi G. 1978. A comparison of Zagros geology to island arcs. J Geol 86, 323–334.

Hassanzadeh J. 1993. Metallogenic and tectonomagmatic events in the SE sector of Cenozoic active continental margin of Central Iran (Shahre-babak area), Kerman province. PhD thesis, University of California, Los Angeles, USA.

Hessami K, Jamali F, Tabassi H. 2003. Map of major active faults of Iran, scale 1:2500000, International Institute of Earthquake Engineering and Seismology, Tehran.

Hofmann AW, Jochum KP, Seufert M, White WM. 1986. Nb and Pb in oceanic basalts: new constraints on mantle evolution. Earth and Planetary Science Letters 79, 33-45.

Irvine TN, Baragar WRA. 1971. A guide to chemical classification of common volcanic rocks., Canadian Journal of Earth Sciences 8, 523-547.

Jackson J, McKenzie D. 1984. Active tectonics of the Alpine-Himalayan belt between western turkey and Pakistan. Geophysical Journal International 77, 185-264.

Mc Clusky S, Reilinger R, Mohmoud S, Bensari D, Tealeb A. 2003. Gpseonstrains on Africa (Nubia) and Arabia plate motion. Geophysical Journal International 155, 126-138.

Mehvari R. 2009. Petrological and mineralogical studies of the hydrothermal alteration (bentonization and silicification), molla ahmad stighiu (east of Isfahan). MSc thesis, University of Isfahan, Isfahan, Iran (in Persian).

MoClusky S, Balassanian S, Barka A, Demir G, Ergintav S, Georgiev G, Gurkan D, Hamburger M, Hurst K, Kahle H, Kastens K, Kekelidze G, King R, Kotzev V, Lenk O, Mohmoud S, Mishin A, Ndariy M, Ouzounis A, Paradissis D, Peter Y, Prilepin M, Reilinger R, Sanli Z, Seeger H, Tealeb A, Toksoz MN, Veis G. 2000. Global positioning system constraints on plate kinematics and dynamics in the eastern Mediterranean and Caucasus. Journal of Geophysical Research 105, 5695-5719.

Parad MA, Nystrom JO, Levi B. 1999. Multiple source for the Coastal Batholith of Central Chile, geochemical an Sr-Nd isotopic evidence and tectonic implication. Lithos 46, 505-521.

Rutherford MJ. 1993. Experimental petrology applied to volcanic processes. American Geophysical Union 74, 49-52.

Sayari M. 2015. Petrogenesis and evolution of Oligocene- Pliocene volcanism in the central part of Urumieh-Dokhtar Magmatic Arc (NE of Isfahan).Phd thesis, University of Isfahan, Isfahan, Iran (in Persian).

Shahabpour J. 2005. Tectonic evolution of the orogenic belt in the region located between Kerman and Neyriz. J Asian Earth Sci 24, 405–417.

Taylor SR, McLennan SM. 1985. The Continental Crust: its Composition and Evolution. Blackwell, Cambridge. 312 p.

Winchester JA, Floyd PA. 1977. Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chemical Geology 20, 325–343.