Hydrous aluminosilicate metasomatism in an intra-oceanic subduction zone: Implications from the Kurancali (Turkey) ultramafic-mafic cumulates within the Alpine Neotethys Ocean

The Kurancali ultramafic-mafic cumulate body, an allochthonous ophiolitic sliver in central Anatolia, is characterized by the presence of abundant hydrous phases (phlogopite, pargasite) besides augitic diopside, plagioclase, and accessory amounts of rutile, sphene, apatite, zircon, and calcite. Based on modes of the essential minerals, the olivine-orthopyroxene-free cumulates are grouped as clinopyroxenite, hydrous clinopyroxenite, phlogopitite, hornblendite, layered gabbro, and diorite. Petrographical, mineralogical and geochemical features of the rocks infer crystallization from a hydrous magma having high-K calcalkaline affinity with slightly alkaline character, and point to metasomatised mantle as the magma source. Our evidence implies that the metasomatising component, which modified the composition of the mantle wedge source rock in an intraoceanic subduction zone, was a H2O, alkali and carbonate-rich aluminosilicate fluid and/or melt, probably derived from a subducted slab. We suggest that the metasomatic agents in the subarc mantle led to the generation of a hydrous magma, which produced the Kurancali cumulates in an island-arc basement in a supra-subduction-zone setting during the closure of the Izmir-Ankara-Erzincan branch of the Alpine Neotethys Ocean.


Environmental effect and genetic influence: a regional cancer predisposition survey in the Zonguldak region of Northwest Turkey
KADİR, Selahattin; Onen-Hall, A. Piril; Aydin, S. Nihal; Yakicier, Cengiz; Akarsu, Nurten; Tuncer, Murat (Springer Science and Business Media LLC, 2008-03-01)
The Cretaceous-Eocene volcano-sedimentary units of the Zonguldak region of the western Black Sea consist of subalkaline andesite and tuff, and sandstone dominated by smectite, kaolinite, accessory chlorite, illite, mordenite, and analcime associated with feldspar, quartz, opal-CT, amphibole, and calcite. Kaolinization, chloritization, sericitization, albitization, Fe-Ti-oxidation, and the presence of zeolite, epidote, and illite in andesitic rocks and tuffaceous materials developed as a result of the degrad...
Intrusive products of H2O and CO2 rich alkaline melt (Karakoç Magmatic Association): Significance in tethyan realm, Turkey
Toksoy Köksal, Fatma (null; 2012-10-01)
The Karakoç Magmatic Association (KMA) within the Central Anatolian Crystalline Complex (CACC) consists of ultramafic cumulates, layered gabbros and diorite. The KMA intruded the carbonate dominated upper part of the CACC as a network and includes host rock xenoliths. The KMA is characterized by abundance of Ca-rich phases (green diopside (Mg#=57-93), pargasite (Mg#=41-86), plagioclase (An=91-95), scapolite (Me=42-92), calcite) and Ca-free minerals (phlogopite (Mg#=71-76), alkali-feldspar). The accessories...
Extrusive members of postcollisional A-type magmatism in Central Anatolia: Karahidir Volcanics, Idis Dagi-Avanos Area, Turkey
Koksal, S; Göncüoğlu, Mehmet Cemal; Floyd, PA (2001-08-01)
The Idis Dagi Igneous Complex is one of a number of late-stage plutonic bodies within the Central Anatolian Crystalline Complex. It intrudes Paleozoic-Mesozoic metamorphic basement rocks and Late Cretaceous granitoids. The complex comprises mainly quartz syenites and alkali-feldspar quartz syenites known as the Idis Dagi Syenitoids.
Structural interpretation of gabbroic rocks in Agacoren Granitoid, central Turkey: field observations and aeromagnetic data
Kadioglu, Yk; Ates, A; Güleç, Nilgün Türkan (1998-03-01)
Gabbroic rocks crop out commonly in different localities of the Central Anatolian Crystalline Complex and are interpreted by many researchers as the remnants of a Neotethyan ophiolitic suite now observed as roof-pendants in the granitoids of the complex. In this study, the structural position of the gabbroic rocks within one of the granitoids of the Central Anatolian Crystalline Complex, namely the Agacoren Granitoid, is determined by geological and aeromagnetic data from the central part of the pluton. The...
Petrology of the Kurancali phlogopitic metagabbro: An island arc-type ophiolitic sliver in the Central Anatolian Crystalline Complex
Toksoy-Köksal, Fatma; Göncüoğlu, Mehmet Cemal; Yalınız, Mustafa Kenan (2001-07-01)
The Kurancali metagabbro occurs as an isolated body in the central part of the Central Anatolian Crystalline Complex. It has been emplaced along a steep S-vergent thrust-plane onto the uppermost units of the Central Anatolian Metamorphics. The main body of the Kurancali metagabbro is characterized by distinct compositional layering. The layered gabbros comprise pyroxene and hornblende gabbros. Phlogopite-rich, plagioclase-hornblende gabbro occurs mainly as pegmatitic dikes intruding the layered gabbro seque...
Citation Formats
F. Toksoy Köksal and M. C. Göncüoğlu, “Hydrous aluminosilicate metasomatism in an intra-oceanic subduction zone: Implications from the Kurancali (Turkey) ultramafic-mafic cumulates within the Alpine Neotethys Ocean,” MINERALOGY AND PETROLOGY, pp. 273–290, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31149.