Delamination Magmatism in Eastern Anatolia: A Geochemical Perspective

Autor: Alican Aktağ, Kaan Sayit, Tanya Furman, Bradley J. Peters
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Geochemistry, Geophysics, Geosystems, Vol 25, Iss 5, Pp n/a-n/a (2024)
Druh dokumentu: article
ISSN: 1525-2027
DOI: 10.1029/2024GC011444
Popis: Abstract The Sr‐Nd‐Hf‐Pb isotope geochemistry of the Late Miocene Tunceli Volcanics suggests that they are the products of mixed asthenospheric and lithospheric mantle melts. The combined elemental and mineral chemistry data additionally indicate that a pyroxenite component of lithospheric origin is involved in their genesis. Calculations favor melting depths of ∼2 GPa for the Tunceli lavas, that is, deeper than the current lithosphere‐asthenosphere boundary beneath Eastern Anatolia. Geochemical data suggest that during regional Neo‐Tethyan subduction, dense (i.e., pyroxenite‐bearing) domains formed by progressive melt intrusion into the lower lithosphere resulted in gravitational instabilities. This unstable density configuration eventually led to the foundering of the eastern Anatolian lithosphere in the Late Miocene, resulting in progressive melting of fusible pyroxenite‐bearing domains at asthenospheric depths. We demonstrate that these pyroxenitic melts mixed with ambient asthenospheric melts and generated the Tunceli lavas.
Databáze: Directory of Open Access Journals