3 research outputs found
Late Cenozoic post-subduction tectonic, magmatic and metallogenic evolution of the Anatolide-Tauride Orogenic Belt, Turkey
The termination of the northward subduction of the Southern Neotethyan oceanic slab
beneath the Anatolide-Tauride Block in Turkey led to the onset of the Arabia-Eurasia
continental collision in the Oligocene. The subducting Southern Neotethyan slab was affected
by post-subduction segmentation manifested by slab break-off (central-eastern Anatolia) and
tearing (western Anatolia) during the late Cenozoic. Many igneous complexes formed in the
late Cenozoic and some of them host gold-rich porphyry and epithermal prospects and deposits.
New temporal (U-Pb, ⁴⁰Ar/³⁹Ar and Re-Os dates), spatial (field observations and GIS) and
geochemical data (elemental and Sr-Nd-Pb isotopic analyses) provide robust constraints on the
genetic relationship between late Cenozoic slab segmentation tectonic events, Anatolian
magmatism and associated gold mineralization.
The newly-defined Eastern Anatolian Magmatic Belt formed in response to the slab
break-off initiation at ca. 25 Ma, window opening, westward break-off propagation to central
Anatolia and induced asthenospheric flow. The slab break-off-related igneous units were
subsequently covered by widespread volcanic products in eastern Anatolia (12 Ma – Present)
that resulted from the long-lived asthenospheric heating, destabilization of the thickened
Anatolian lithosphere root and its partial removal by convective dripping. Magmatic sources
include the shallow melting of the previously-metasomatized Anatolian subcontinental
lithospheric mantle and asthenosphere by decompression due to impingement of the Arabian
and African sub-slab asthenospheric mantles.
Late Cenozoic Anatolian magmatism produced porphyry and epithermal prospects and
deposits that cluster in nine isolated mineral districts controlled by graben, transtensional
corridors and pull-apart basins. The bulk of gold mineralization (33 Moz Au) peaked at the
beginning of the slab break-off event at 25 Ma in central and eastern Anatolia, and slab tear at
15 Ma in western Anatolia.
The late Cenozoic trench-parallel and -perpendicular migrations of slab rupture and
window opening in Anatolia 1) allowed toroidal and poloidal flow of asthenosphere beneath
Anatolia, 2) caused the migration of melting source and associated igneous complexes and
mineral deposits in the overriding crust, 3) destabilized the Anatolian lithospheric mantle,
which reduced the amount of available volatiles and metals, and therefore 4) increased the
production of barren, drier and mantle-dominant volcanism through time that partially covers
fertile igneous units.Science, Faculty ofEarth, Ocean and Atmospheric Sciences, Department ofGraduat