Coeval Shoshonitic-ultrapotassic dyke emplacements within the Kestanbol Pluton, Ezine – Biga Peninsula (NW Anatolia)

The Biga Peninsula, in the north-western part of Western Anatolia, is part of the Sakarya Zone of the Western Pontides and the tectonically overlying Ezine group. The basement rocks are intruded by the early Miocene Kestanbol Pluton and early to middle Miocene calc-alkaline to shoshonitic-ultrapotassic volcanic successions related to postcollisional continental extension. The Kestanbol Pluton mainly comprises monzonite and granodiorite and is cut by shoshonitic-ultrapotassic tephriphonolite dykes. 40Ar-39Ar ages of biotite (21.22 ± 0.09 Ma) and leucite (22.21 ± 0.07 Ma) crystals indicate that tephriphonolite dyke emplacement was coeval with the intrusion of the Kestanbol Pluton during the early Miocene (21.5 ± 1.6, 22.8 ± 0.2 Ma). The geochemical features of the tephriphonolite dykes suggest a phlogopite-bearing mantle source which may originate from a previously metasomatised subcontinental lithospheric mantle source. This mantle source shows the imprints of carbonate-reach oceanic sediment recycling and crustal material contamination processes, which evolved during northward subduction and closure of the northern branch of the Neo-Tethys Ocean beneath the Sakarya zone during the late Cretaceous to Eocene.

Coeval Shoshonitic-ultrapotassic dyke emplacements within the Kestanbol Pluton, Ezine – Biga Peninsula (NW Anatolia)

The Biga Peninsula, in the north-western part of Western Anatolia, is part of the Sakarya Zone of the Western Pontides and the tectonically overlying Ezine group. The basement rocks are intruded by the early Miocene Kestanbol Pluton and early to middle Miocene calc-alkaline to shoshonitic-ultrapotassic volcanic successions related to postcollisional continental extension. The Kestanbol Pluton mainly comprises monzonite and granodiorite and is cut by shoshonitic-ultrapotassic tephriphonolite dykes. 40Ar-39Ar ages of biotite (21.22 ± 0.09 Ma) and leucite (22.21 ± 0.07 Ma) crystals indicate that tephriphonolite dyke emplacement was coeval with the intrusion of the Kestanbol Pluton during the early Miocene (21.5 ± 1.6, 22.8 ± 0.2 Ma). The geochemical features of the tephriphonolite dykes suggest a phlogopite-bearing mantle source which may originate from a previously metasomatised subcontinental lithospheric mantle source. This mantle source shows the imprints of carbonate-reach oceanic sediment recycling and crustal material contamination processes, which evolved during northward subduction and closure of the northern branch of the Neo-Tethys Ocean beneath the Sakarya zone during the late Cretaceous to Eocene.

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Akal, C. 2008. K-richterite-olivine-phlogopite-diopside-sanidine lamproites from the Afyon Volcanic Province, Turkey. Geological Magazine 145, 1-16.

Akal, C., Candan, O., Koralay, O.E., Oberhänsli, R. Chen, F. & Dejan, P. 20 Early Triassic potassic volcanism in the Afyon Zone of the Anatolides/Turkey: implications for the rifting of the NeoTethys. International Journal of Earth Sciences (Geologische Rundschau) 101, 177-194. Akal, C., Koralay, O.E., Candan, O., Oberhänsli, R. & Chen, F. 2011. Geodynamic significance of the early Triassic Karaburun granitoid (Western Turkey) for the opening history of NeoTethys. Turkish Journal of Earth Sciences 20, 255-271.

Aldanmaz, E. 2002. Mantle source characteristics of alkali basalts and basanites in an extensional intracontinental plate setting, western Anatolia, Turkey: implications for multi-stage melting. International Geological Review 44, 440-457.

Aldanmaz, E., Gourgaud, A. & Kaymakcı, N. 2005. Constraints on the composition and thermal structure of the upper mantle beneath NW Turkey: Evidence from mantle xenoliths and alkali primary melts. Journal of Geodynamics 39, 277-316. Aldanmaz, E., Köprübaşı, N., Gürer, O.F., Kaymakcı, N. & Gourgaud, A. 200 Geochemical constraints on the Cenozoic, OIB-type alkaline volcanic rocks of NW Turkey: implications for mantle sources and melting processes. Lithos 86, 50-76.

Aldanmaz, E., Pearce, J.A., Thirlwall, M.F. & Mitchell, J.G. 2000. Petrogenetic evolution of Late Cenozoic, post-collision volcanism in western Anatolia, Turkey. Journal of Volcanology and Geothermal Research 102, 67-95.

Altunkaynak, Ş., Dilek, Y., 2006. Timing and nature of postcollisional volcanism in western Anatolia and geodynamic implications. In: Dilek, Y. & Pavlides, S. (eds.), Postcollisional Tectonics and Magmatism in the Mediterranean Region and Asia. Geological Society of America Special Paper, 409, 321-351.

Altunkaynak, Ş., Dilek, Y., Genç, C.Ş., Sunal, G., Gertisser, R., Furnes, H., Foland, K.A. & Yang, J. 2012. Spatial, temporal and geochemical evolution of Oligo–Miocene granitoid magmatism in western Anatolia, Turkey. Gondwana Resarch, 21, 961-986.

Turkish Journal of Earth Sciences-Cover
  • ISSN: 1300-0985
  • Yayın Aralığı: Yılda 6 Sayı
  • Yayıncı: TÜBİTAK
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