Volcanic Rocks from Foca-Karaburun and Ayvalik-Lesvos Grabens (Western Anatolia) and Their Petrogenic-Geodynamic Significance

Agostini S., TOKCAER M., Savascin M. Y.

TURKISH JOURNAL OF EARTH SCIENCES, cilt.19, sa.2, ss.157-184, 2010 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 19 Sayı: 2
  • Basım Tarihi: 2010
  • Doi Numarası: 10.3906/yer-0905-11
  • Dergi Adı: TURKISH JOURNAL OF EARTH SCIENCES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, TR DİZİN (ULAKBİM)
  • Sayfa Sayıları: ss.157-184
  • Anahtar Kelimeler: Turkish Aegean region, volcanic rocks, extension tectonics, Cenozoic, geochemistry, petrology, BUYUK-MENDERES GRABEN, NEOTECTONIC STRUCTURES, EXTENSIONAL TECTONICS, SURROUNDING REGIONS, 2-STAGE EXTENSION, GEDIZ GRABEN, EVOLUTION, TURKEY, MASSIF, AGE
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

The Foca-Karaburun and Ayvalik-Lesvos grabens (western coast of Anatolia, Turkey) are two important NW-SE-trending extensional areas generated in response to the Early Miocene-Holocene extension of the Western Anatolian region, related to the opening of the 'unconventional' back-arc basin of the Aegean Sea. The abundance of geo-structural evidence and the occurrence of volcanic rocks representing all the stages of the Aegean-Western Anatolia volcanism render the Foca-Karaburun and Ayvalik-Lesvos Grabens key localities to exemplify the petrogenetic and geodynamic evolution of the area. In this context, the Foca-Karaburun and Ayvalik-Lesvos grabens, possibly formerly a single graben, formed along an original NE-SW-trending extension, later dissected by E-W-trending transtensional faults, are investigated to constrain the petrogenetic and geodynamic evolution of the whole Aegean region. Calc-alkaline and shoshonitic volcanic rocks with scattered ultrapotassic-shoshonitic or lamproitic lavas and dykes represent the orogenic phase of the magmatic activity, while the younger K-and Na-rich alkaline basaltic rocks are the result of later magmatism characterized by an intraplate geochemical signature reflecting progressively decreasing subduction rates.