Migrating magmatism in a continental arc: Geodynamics of the Eastern Mediterranean revisited


Eyuboglu Y., Santosh M., Dudas F. O., Chung S., Akaryali E.

JOURNAL OF GEODYNAMICS, vol.52, no.1, pp.2-15, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 52 Issue: 1
  • Publication Date: 2011
  • Doi Number: 10.1016/j.jog.2010.11.006
  • Journal Name: JOURNAL OF GEODYNAMICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2-15
  • Keywords: Adakite, Isotopes, Geodynamics, Ridge subduction, Slab window, Eastern Pontides, BLACK-SEA BASIN, EXPERIMENTAL CONSTRAINTS, TECTONIC EVOLUTION, RIDGE SUBDUCTION, INTRUSIVE ROCKS, MANTLE WEDGE, SUTURE ZONE, PONTIDES, VOLCANISM, GEOCHEMISTRY
  • Karadeniz Technical University Affiliated: No

Abstract

The eastern Pontide orogenic belt in Turkey offers a critical region to evaluate the geodynamic evolution of the eastern Mediterranean region during the late Mesozoic-Cenozoic. Here we synthesize results from our exhaustive database on the geochemical characteristics of adakitic magmatism from 137 bodies covering 7 domains in the southern zone of eastern Pontides. Together with new Pb-Sr-Nd results, we show that the adakitic magmatism in the eastern Pontide belt is clearly linked to slab window processes during ridge subduction, as against the earlier models that assumed partial melting of a delaminated or thickened lower continental crust following collision. The isotopic compositions display a complex pattern and suggest mixing of multiple source materials such as depleted mantle, enriched lithospheric mantle, and upper crust. We also confirm a southward polarity of subduction as against the previous models that assumed a northward subduction. We supplement our model with evidence for a northward propagation of the adakitic magmatism, spatial and temporal variations in arc magmatism, presence of south-dipping reverse faults and a synthesis of the available paleomagnetic data. Our studies also suggest that the Black-Sea is a remnant of the Tethyan ocean that was situated to the north of the arc during the late Mesozoic-Cenozoic as against the correlation to a late Mesozoic-Cenozoic back-arc basin related to a northward subduction of the Paleo- or Neo-tethyan oceanic lithosphere in alternate models. (C) 2010 Elsevier Ltd. All rights reserved.