Geochemical and Isotopic Constraints on Petrogenesis of the Beypazari Granitoid, NW Ankara, Western Central Anatolia, Turkey
TURKISH JOURNAL OF EARTH SCIENCES, cilt.21, sa.1, ss.53-77, 2012 (SCI-Expanded, Scopus, TRDizin)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 21 Sayı: 1
- Basım Tarihi: 2012
- Doi Numarası: 10.3906/yer-1006-1
- Dergi Adı: TURKISH JOURNAL OF EARTH SCIENCES
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, TR DİZİN (ULAKBİM)
- Sayfa Sayıları: ss.53-77
- Anahtar Kelimeler: Beypazari granitoid, Upper Cretaceous, oxygen and hydrogen isotopes, crustal contamination, western-central Anatolia, Turkey
- Dokuz Eylül Üniversitesi Adresli: Evet
Özet
The Upper Cretaceous Beypazari granitoid of the western Ankara, Turkey, is composed of two different units, on the basis of petrography and geochemical composition; these are granodiorite and diorite. The granitoid is subalkaline, belonging to the high-K calc-alkaline I-type granite series, which have relatively low initial Sr-87/Sr-86 ratios (0.7053-0.7070). All these characteristics, combined with major, trace element geochemical data as well as mineralogical and textural evidence, reveal that the Beypazari granitoid formed in a volcanic arc setting and was derived from a subduction-modified and metasomatized mantle-sourced magma, with its crustal and mantle components contaminated by interaction with the upper crust. The rocks have epsilon Nd-(75Ma) values ranging from -5.5 to -2.0. These characteristics also indicate that a crustal component played a very important role in their petrogenesis.