Document Type : Original Research Paper

Authors

1 M.Sc. Student, Department of Geology, University of Sistan and Baluchestan, Zahedan, Iran

2 Associate Professor, Department of Geology, University of Sistan and Baluchestan, Zahedan, Iran

3 Assistance Professor, Department of Geology, University of Sistan and Baluchestan, Zahedan, Iran

Abstract

The volcanic rocks of Kuleh sangi-Malek siah kuh igneous complex consist of alkalibasalt, basalt, basaltic andesite, andesite, dacite and trachyte. In the SiO2 versus K2O diagram, the basaltic samples are plotted in the shoshonitic field and the subalkaline samples are plotted in the medium K calc alkaline series field. The average La/Yb, Rb/Zr and Cs/Hf ratios in basalts are 7, 47 and 63 times those of N-MORB, respectively. Considerable enrichment of LILEs, LREEs and relative depletion of HREEs indicate that the magmas originated from a mantle source more enriched than that of OIB, where phlogopite and garnet are stable. Using non-modal batch melting model, the compositions of the mafic samples are mainly consistent with about 5% melting of a phlogopite-bearing and garnet-bearing lherzolite with a mixture of about 80% and 20%, respectively. AFC models using Pb versus Ce/Pb and Rb versus K/Rb, show that the fractionated samples have undergone simultaneous crustal assimilation and fractional crystallization. It seems that the assimilation and the fractionation had been taken place with the same rate. Depletion in Y and elevated ratio of Sr/Y of fractionated rocks in addition to Rb/Nb ratio more than 8, could be considered as evidence for crustal assimilation.

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References
Albarede, F., 1995- Introduction to Geochemical Modeling. Cambridge University Press. New York, USA, 543 p.
Aldanmaz, E., 2002- Mantle source characteristics of alkali basalts and basanites in an extensional intracontinental plate setting, western Anatolia, Turkey: implication for multi-stage melting. International Geology Review 44, 440- 457.
Aldanmaz, E., Koprubasi, N., Gurer, O. F., Kaymakci, N. and Gourgaug, A., 2006- Geochemical       constraints on the Cenozoic, OIB- type alkaline volcanic rocks of NW Turkey: Implications for mantle sources and melting processes. Lithos 86: 50- 76.
Bau, M., 1991- Rare-earth element mobility during hydrothermal and metamorphic fluid-rock interaction and the significance of the oxidation state of europium. Chemical Geology, 93 (3- 4): 219- 230.
Camp, V. E. and Griffis, R. J., 1982- Character, genesis and tectonic Setting of igneous rock in the Sistan suture zone of eastern       Iran. Lithos, 15: 221- 239.
Chapman, A. D., Ducea, M. N., Kidder, S. and Petrescu, L., 2014- Geochemical constraints on the petrogenesis of the Salinian arc, central California: Implications for the origin of intermediate magmas. Lithos, 200- 201: 126- 141.
Chazot, G. and Bertrand, H., 1995- Genesis of silicic magma during Tertiary continental rifting inYemen. Lithos, 36: 69- 83.
Davidson, J., Turner, S., Handley, H., Macpherson, C. and Dosseto, A., 2007- An amphibole ‘sponge’ in arc crust? Geology 35,    787- 790.
Deer, W. A., Howie, R. A. and Zussman, J., 1996- An Introduction to the Rock Forming Minerals (2nd ed.). Longman, Essex, 696p.
De Paolo, D. J., 1981- Trace element and isotopic effects of combined wall-rock assimilationandfractional crystallization. Earth and Planetary Science Letters, 53: 189- 202.
Doroozi, R., Garmela, V., Masoudi, F. and Petrini, R., 2018- Petrogenesis and mantle source of Triassic alkaline basaltic rocks of north Kamarbon, northern central Alborz, Iran. Solid Earth Sciences xx: 1-15.
Eftekharnezhad, J., 1993- Geological map of Zahedan, 1:100000, Geological Survey of Iran, Tehran.
El-Bialy, M. Z., 2010- On the Pan-African transition of the Arabian-Nubian Shied from compression to extension: the post-collision Dokhan volcanic suite of Kid-Malhal region, Sinai, Egypt. Gondwana Research, 17: 26- 43.
Fitton,  J. G., 1987- The Cameroon line, West Africa: a comparison between oceanic and    continental alkaline volcanism. In: Fitton, J. G. & Upton, B. G. J. (eds) Alkaline Igneous Rocks, Geological Society Special Publication No. 30, pp. 273- 291.
Gao, Y., Santosh, M., Hou, Z., Wei, R., Ma, G., Chen, Z. and Wu, J., 2012- High Sr/Y magmas generated through crystal fractionation: evidence from Mesozoic volcanic rocks in the northern Taihang orogen, North China Craton. Gondwana Research, 22: 152- 168.
Irvine, T. N. and Baragar, W. R. A., 1971- A guide to the chemical classification of the common rocks. Canadian Journal of Earth Sciences, 8: 523- 548.
Johannsen, A., 1939- A Descriptive Petrography of Igneous Rocks, vol 4 (2nd ed.) University of Chicago press, Chicago, 523p.
Kay, R. W. and Cast, P. W., 1973- the Rare Earth content and origin of alkali-rich basalts. Journal of geology, 81: 553- 682.
Kay, S. M. and Kay, R. W., 1994- Aleutian magmas in space and time. In: G. Plafker, H. C.Berg (Eds) The Geology of Alaska:       Geologocal Society of America, 687- 722.
Kheirkhah, M., Nail, I. and Allen, M. B., 2015- Petrogenesis of OIB-like basaltic volcanic rocks in a continental collision zone: Late Cenozoic magmatism of Eastern Iran. Journal of Asian Earth Sciences 106: 19- 33.
Kosler, J., Magna, T., Micoch, B. and Holub, F., 2009- Combined Sr, Nd, Pb and Li isotope geochemistry of alkaline lavas from northern James Ross Island and Implications for back arc magma formation. Chemical Geology 258: 207- 218.
Kretz, R., 1983- Symbols for rock-forming minerals. Am. Mineral., 68, 277- 279.
Le Maitre, R. W., 2002- Igneous Rocks, a Classification and Glossary of Terms. Cambridge University Press, New York, 236 P.
McKenzie, D. and O'Nions, R. K., 1991- Partial melt distributions from inversion of rare earth element concentrations. Journal         of Petrology, 2: 1021- 1091.
Nelson, S. A., Gonzalez-Caver, E. and Kyser T. K., 1995- Constraints on the origin of alkaline and calc- alkaline magmas from the Tuxtla Volcanic Field, Veracruz, Mexico. Contributions to Mineralogy and Petrology, 122:191- 211.
Niu, Y., 2008- the origin of alkaline lavas. Science 320: 883- 884.
Nono, A., Deruelle, B., Demaiffe, D. and Kambou, R., 1994- Tchabal Nganha Volcano in adamawa (Cameroon) petrology of the     continental alkaline lava series. Journal of Volcanology and Geothermal Research 60: 147- 178.
Ozdemir, Y. and Gulec, N., 2014- Geological and Geochemical Evolution of the Quaternary Suphan Stratovolcano, Eastern Anatolia, Turkey: Evidence for the Lithosphere-Asthenosphere Interaction in Post-Collisional Volcanism. Journal of Petrology, 55: 37- 62.
Paton, S. M., 1992- The relationship between extension and volcanism in western Turkey, the Aegean Sea and Central      Greece. Unpublished PhD thesis, Cambridge University.
Pearce, J. A., 2008- Geochemical fingerprinting of oceanic basalts with applications to ophiolite classification and the search for Archean oceanic crust. Lithos 100: 14- 48.
Peccerillo, A. and Taylor, S. R., 1976- Geochemistry of Eocene Calc-alkaline Volcanic rocks from the Kastamonu area, northern Turkey. Contribution to Mineralogy and Petrology, 58: 63- 81.
Plank, T. and Langmuir, C. H., 1993- Tracing trace elements from sediment input to volcanic output at subduction zones. Nature 362: 739- 743.
Rollinson, H. R., 1996- Using Geochemical Data: Evaluation, Presentation, Interpretation. Longman Scientific & Technical publish, 352 p.
Rudnick, R. L. and Gao, S., 2003- Composition of the continental crust, In: R.L. Rudnick (ed.)  Treatise on Geochemistry 3: 1- 64. Amesterdam, Elsevier.
Shaw, D. M., 1970- Trace element fractionation during anataxis. Geochimica et Cosmochimica Acta, 34: 237- 243.
Skewes, M. A. and Stern, C. R., 1979- Petrology and geochemistry of alkali basalts and ultramafic inclusions from the Palei - Aike volcanic field in southern Chile and the origin of the Patagonian Plateau lavas. Journal of Volcanology and Geothermal Research 6: 3- 25.
Sun, S. S. and McDonough, W. F., 1989- Chemical and isotopic system of oceanic basalts: implications for mantle composition and processes. Geological Society of London Special Publication, 42: 313- 345.                
Taylor, S. R. and McLennan, S. M., 1995- The geochemical evolution of continental crust. Reviews in Geophysics, 33:241- 256.
Tirrul, R., Bell, I. R., Griffis, R. J. and Camp, V. E., 1983- The Sistan suture zone of eastern Iran. Geological Society of America  Bulletin 94: 134- 150.
White, W. M., 2013- Geochemistry. Wiley-Blackwell, California, 668 p.
Williams, H., Turner F. J. and Gilbert, C. M., 1982- Petrography an Introduction to the Study of Rocks in Thin Sections. Freeman, New York, 626 p.
Wilson, M. and Downes, H., 1991- Tertiary-quaternary extension related alkaline magmatism in western and central Europe. Journal of Petrology 32: 811- 849.
Wilson, M., 1989- Igneous Petrogenesis. Unwin Hyman Ltd, Londom, 466 p.