Contemporaneous Late Cretaceous Calc-alkaline and Alkaline Magmatism in Central Anatolia, Turkey: Oxygen Isotope Constraints on Petrogenesis

İLBEYLİ N., PEARCE J. A., Meighan I. G., FALLICK A. E.

TURKISH JOURNAL OF EARTH SCIENCES, cilt.18, sa.4, ss.529-547, 2009 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 18 Sayı: 4
  • Basım Tarihi: 2009
  • Doi Numarası: 10.3906/yer-0811-8
  • Dergi Adı: TURKISH JOURNAL OF EARTH SCIENCES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, TR DİZİN (ULAKBİM)
  • Sayfa Sayıları: ss.529-547
  • Anahtar Kelimeler: I-type granite, A-type granite, oxygen isotope, Kaman-Kirsehir region, central Anatolia, Turkey, EASTERN-CENTRAL ANATOLIA, K-AR AGE, CRUSTAL CONTAMINATION, GEOCHEMICAL CONSTRAINTS, CRYSTALLINE COMPLEX, EXHUMATION HISTORY, TRACE-ELEMENT, WHOLE-ROCK, GRANITOIDS, RATIOS
  • Akdeniz Üniversitesi Adresli: Hayır

Özet

A wide variety of rock types were produced by the latest Cretaceous magmatism in the Central Anatolian Crystalline Complex. These rocks can be divided into three distinct units: (i) calc-alkaline, (ii) subalkaline/transitional, and (iii) alkaline. The calc-alkaline rocks are mainly metaluminous (I-type) ranging from monzodiorite to granite. The subalkaline/ transitional rocks are also metaluminous (I-type) ranging from monzonite to granite. The alkaline rocks are mainly peralkaline (A-type), ranging from feldspathoid-bearing monzosyenite to granite. Whole-rock oxygen isotope data from the complex have a considerable range of delta O-18 values between 6.5% and 14.8%. Initial Sr-87/Sr-86 versus Nd-143/Nd-144 ratios, and both ratios versus d18O values diagrams show that the intrusive rocks are derived from a subduction-modified mantle and also have experienced fractional crystallisation coupled with crustal assimilation. Delamination of a thermal boundary layer, and/or slab breakoff is the likely mechanisms for the initiation of the diverse magmatism in the complex.