Petrographic and Geochemical Fingerprints of Sub-Volcanic Dykes and their Host Harzburgites from the Ulaş Ultramafics Sivas, Turkey

Year 2020, Volume: 2 Issue: 1, 1 - 12, 01.04.2020

Özgür Bilici Hasan Kolaylı Ekrem Kalkan Tuğba Bilici Necmi Yarbaşı

Abstract

In the southern Ulaş region Sivas, mid-Anatolia , the ophiolitic fragments of the Neotethys oceanic lithosphere are widespread. The study area consists of commonly harzburgite, with minor dunite and chromitite pods and also pyroxenites. The latter are sub-volcanic gabbro and diabase dykes. In this study, the petrographic and geochemical importance of the mantle harzburgites and the sub-volcanic dykes cutting them were evaluated, within these ophiolitic units. The textural properties of the harzburgites were generally anhedral, granular and partially poikilitic. They consisted of olivine, orthopyroxene and minor amount of clinopyroxene and chromian spinel. On the other hand, the textural and mineralogical characteristics of sub-volcanic dykes, consisted of plagioclase, pyroxene, hornblende, opaque minerals and their secondary products, reflected semi-depth characters. The major, trace and rare earth element compositions indicated that the harzburgites were similar to that of both abyssal and supra-subduction SSZ peridotites with depleted character. Furthermore, the sub-volcanic dykes that formed the focus of this study in the mantle harzburgites exhibited N-MORB Normal Mid-Ocean Ridge Basalt type patterns of rare earth REE and trace elements. Especially, negative Nb anomaly showed the presence of a subduction component with the late stage modification of subduction-derived fluids/melts. All results indicated that the dykes characterized as N-MORB and late recorded the characteristics of Ocean Island Basalts OIB . Consequently, geochemical features of the harzburgites and sub-volcanic dykes that cut them showed that peridotites were affected by two different tectonic setting conditions such as MORB and SSZ.

Keywords

peridotites, sub-volcanic dyke, subduction zone, Ulaş ultramafics, Sivas

References

• Andrew, T., Robertson, A.H.F., 2002. The Beyflehir-Hoyran- Hadim nappes: genesis and emplacement of Mesozoic marginal and oceanic units of the northern Neotethys in southern Turkey. Journal of the Geological Society 159, 529-543.
• Bilici, Ö., 2015. Comparative investigation of Kop (Erzurum- Erzincan-Bayburt), Ulaş (Sivas) and Yeşilova (Burdur) ultramafics and chromitites in terms of mineralogical, petrological and geodynamical aspects. PhD, Karadeniz Technical University, Trabzon, Turkey (in Turkish with English Abstract).
• Bilici, Ö., Kolayli, H., 2018. Mineral records of the pyroxenites formed within harzburgites (Ulaş, Sivas, Turkey): implications on petrogenesis and tectonic setting. Turkish Journal of Earth Science 27, 384-404.
• Cater J.M.L., Hanna, S.S., Ries, A.C., Turner, P., 1991. Tertiary evolution of the Sivas Basin, Central Turkey. Tectonophysics, 195, 29-46.
• Coleman, R.G., 1977. Ophiolites, Ancient Oceanic Lithosphere. Belin: Springer-Verlag, 2-10.
• Collins, A.S., Robertson, A.H.F. 1998. Processes of Late Cretaceous to Late Miocene episodic thrust-sheet translation in the Lycian Taurides, SW Turkey. Journal of Geological Society 155, 759-772.
• Çelik, Ö.F., Delaloye, M., 2003. Origin of metamorphic soles and their post-kinematic mafic dyke swarms in the Antalya and Lycian ophiolites, SW Turkey. Geological Journal 38 235-256.
• Dilek, Y., Furnes, H., 2014. Ophiolites and their origins. Elements 10, 93-100.
• Dilek, Y., Thy, P., Hacker, B., Grundvig, S., 1999. Structure and petrology of Tauride ophiolites and mafic dyke intrusions (Turkey): implications for the Neotethyan ocean. Geological Society of America Bulletin 111, 1192-1216.
• Floyd, P.A., Winchester, J.A., 1978. Identification and discrimination of altered and metamorphosed volcanic rocks using immobile elements. Chemical Geology 21, 291-306.
• Hart, S.R., Zindler, A., 1986. In search of a bulk-Earth composition. Chemical Geology 57, 247-267.
• Hartmann, G., Wedepohl, K.H., 1993. The composition of peridotite tectonics from the Ivrea complex, northern Italy, residues from melt extraction. Geochemica et Cosmochemica Acta 57, 1761-1782.
• MTA, 2002. 1:500,000 Scale Geology Map of Turkey. General Directorate of Mineral Research and Exploration, Ankara, Turkey.
• Miller, C., Thöni, M., Frank, W., Schuster, R., Melcher, F., Meisel, T., Zanetti, A., 2003. Geochemistry and tectonomagmatic affinity of the Yungbwa ophiolite, SW Tibet. Lithos 66, 155-172.
• Niu, Y., 2004. Bulk-rock major and trace element compositions of abyssal peridotites: implications for mantle melting, melt extraction and post-melting processes beneath mid-ocean ridges. Journal of Petrology 45, 2423-2458.
• Niu, Y.L., Langmuir, C.H., Kinzler, R.J., 1997.The origin of abyssal peridotites: A new perspective. Earth and Planetary Science Letters 152(1–4), 251-265.
• Okay, I.A., Tüysüz, O., 1999.Tethyan sutures of northern Turkey. Journal of Geological Society, London Special Publication 156, 475-515.
• Parkinson, I.J., Pearce, J.A., 1998.Peridotites from the Izu–Bonin– Mariana forearc (ODP Leg 125), evidence for mantle melting, melt–mantle interaction in a suprasubduction zone setting. Journal of Petrology 39, 1577-1618.
• Parlak, O., 2016.The Tauride ophiolites of Anatolia (Turkey): a review. Journal of Earth Science 27, 901-934.
• Parlak, O., Çolakoğlu, A., Dönmez, C., Sayak, H., Yıdırım, N., Türkel, A., Odabaşı, I., 2013.Geochemistry and tectonic setting of ophiolites along the İzmir–Ankara–Erzincan Suture Zone in northeastern Anatolia. In A.H.F. Robertson, O. Parlak, U.C., Ünlügenç (Eds.), Geological development of Anatolia and the easternmost Mediterranean. London: Geological Society, Special Publications 372, 75-106.
• Parlak, O., Delaloye, M., 1996.Geochemistry and timing of post metamorphic dike emplacement in the Mersin ophiolite (southern Turkey): new age constraints from 40Ar/39Ar geochronology. Terra Nova 8, 585-592.
• Parlak, O., Yilmaz, H., Boztuğ, D., 2006.Origin and tectonic significance of the metamorphic sole and isolated dykes of the Divriği ophiolite (Sivas, Turkey): evidence for slab break-off prior to ophiolite emplacement. Turkish Journal of Earth Science 15, 25-45.
• 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.
• Pearce, J.A., Alabaster, T., Shelton, A.W., Searle M.P., 1981. The Oman Ophiolite as a Cretaceus Arc-basin Complex, Evidence and Implications. Philosophical Transactions of the Royal Society a Mathematical Physical and Engineering Sciences 300, 299-317.
• Pearce, J.A., Cann, J.R., 1973.Tectonic setting of basic volcanic rocks determined using trace element analyses. Earth and Planetary Science Letters 19, 290-300.
• Pearce, J.A., Lıppard, S.J., Roberts, S., 1984.Characteristics and tectonic significance of suprasubduction zone ophiolites. In: Kokelaar, B.P., Howells, M.F. (eds), Marginal Basin Geology. Geological Society, London, Special Publications 16, 77-94.
• Pearce, J.A., Norry, M.J., 1979.Petrogenetic implications of Ti, Zr, Y and Nb variations in volcanic rocks. Contributions to Mineralogy and Petrology 69, 33-47.
• Poisson, A., Guezou, J.C., Öztürk, A., İnan, S., Temiz, H., Gürsöy, H., Kavak, K.S., Özden, S., 1996. Tectonic setting and evolution of the Sivas Basin, Central Anatolia, Turkey. International Geology Review 38, 838-853.
• Robertson, A.H.F., 2002. Overview of the genesis and emplacement of Mesozoic ophiolites in the eastern Mediterranean Tethyan region. Lithos 65, 1-67.
• Robertson, A.H.F., Dixon, J.E., 1984. Introduction: aspects of the geological evolution of the Eastern Mediterranean. In: Dixon, J.E., Robertson, A.H.F. (eds), The Geological Evolution of the Eastern Publications 17, 1-74. Geological Society, Special
• Robertson, A., Parlak, O., Ustaömer, T., Taslı, K., Inan, N., Dumitrica, P., Karaoglan, F., 2013. Subduction, ophiolite genesis and collision history of Tethys adjacent to the Eurasian continental margin: new evidence from the Eastern Pontides, Turkey. Geodinamica Acta 26, 230-293.
• Şengör, A.M.C., Yılmaz, Y., 1981. Tethyan evolution of Turkey: a plate tectonic approach. Tectonophysics 75, 181-241.
• Shervais, J.W. 2001. Birth, death and resurrection: The life cycle of supra-subduction zone ophiolites. Geochemistry Geophysics Geosystems 2, 1-45.
• Ö. Bilici et al. IJESKA (2020) 2 (1) 1-12
• Sun, S.S., McDonough, W.F., 1989. Chemical and isotopic systematics of oceanic basalts: implications for mantle compositions and processes. In: Saunders, A.D., Norry, M.J. (eds.), Magmatism in the Ocean Basins. London: Geological Society, Special Publications 42, 313-345.
• Wood, D.A., 1980. The applications of a Th-Hf-Ta diagram to problems of tectonomagmatic classification and to establishing the nature of crustal contamination of basaltic lavas of the British Tertiary volcanic province. Earth and Planetary Science Letters 50, 11-30.
• Wu, W., Yang, J., Dilek, Y., Milushi, I., Lian, D., 2017. Multiple episodes of melting, depletion, and enrichment of the Tethyan mantle: Petrogenesis of the peridotites and chromitites in the Jurassic Skenderbeu massif, Mirdita ophiolite, Albania. Lithosphere 10(1), 54-78.
• Xu, X., Yang, J., Xiong, F., Guo, G., 2019. Petrology and Geochemistry of the Dangqiong Ophiolite, Western Yarlung- Zangbo Suture Zone, Tibet, China. Acta Geologica Sinica (English Edition) 93(2), 344-361.
• Yılmaz, H., Arıkal, T., Yılmaz, A., 2001. Geology of the Güneş ophiolite (Divriği-Sivas). Proceedings of the 54th Geological Congress of Turkey, Ankara, Turkey, pp. 54-65 (in Turkish with an abstract in English).
• Yilmaz, A., Sümengen, M., Terlemez, I., Bilgiç, T., 1989. 1:100000 Scale Geology Map of Turkey, Sivas G23. General Directorate of Mineral Research and Exploration, Ankara, Turkey.
• Yılmaz, A., Yılmaz, H., 2006. Characteristic features and structural evolution of a post collisional basin: The Sivas Basin, Central Anatolia, Turkey. Journal of Asian Earth Science 27, 164-176.
• Yılmaz, H., Yılmaz, A., 2004. Geology and Structural Evolution of the Divriği (Sivas) Region. Geological Bulletin of Turkey 47, 13