Akademik Veri Yönetim Sistemi
MINERALS, cilt.1, sa.1, ss.1-24, 2022 (SCI-Expanded, Scopus)
Saricakaya-Nallihan Volcanism was generated within the Balkanatolia Magmatic Realm between 48 and 44 Ma (by 40Ar/39Ar age determination) and is represented by three different volcanic units all displaying subduction-related geochemical signatures, such as depletion in HFSE and enrichment in LREE and LILE. The first unit (V1) consists of nepheline-normative, olivine basalts with OIB-like affinity. The second (V2) and third (V3) units are represented by more evolved compositions such as basaltic-andesitic, andesitic, and dacitic-rhyolitic lavas. Even the most basic lavas have elevated Mg# values (62-69), and they are far from representing the true mantle melts. Source characterization of Saricakaya-Nallihan Volcanism reveals that there might be two possible mantle sources for the primary melts of the lavas: (i) metasomatized peridotitic mantle fluxed by sedimentary melts, or (ii) accreted melange. The direct melting of the melange-like lithologies is a more favorable mechanism for the Middle Eocene (44-40 Ma) magmatism in Balkanatolia since the Hf-Nd trace element, Nd isotopic systematics and petrological modelling efforts supported the latter. Overall, Early Cenozoic magmatism within this realm was characterized, first (58-44 Ma) by contractional and later (44-40 Ma) by extensional tectonics and the late-stage magmatic phase in the area was possibly controlled by melting of accreted melange-like lithologies. The presented data indicate that melange melting might be much more common than envisaged for the magmatism in the Alpine-Himalayan orogenic belt.