Abstract
Post-collision magmatic rocks are common in the southern portion of the Marmara region (Kapidaǧ, Karabiga, Gönen, Yenice, Çan areas) and also on the small islands (Marmara, Avşa, Paşalimani) in the Sea of Marmara. They are represented mainly by granitic plutons, stocks and sills within Triassic basement rocks. The granitoids have ages between Late Cretaceous and Miocene, but mainly belong to two groups: Eocene in the north and Miocene in the south. The Miocene granitoids have associated volcanic rocks; the Eocene granitoids do not display such associations. They are both granodioritic and granitic in composition, and are metaluminous, calc-alkaline, medium to high-K rocks. Their trace elements patterns are similar to both volcanic-arc and calc-alkaline post-collision intrusions, and the granitoids plot into the volcanic arc granite (VAG) and collision related granite areas (COLG) of discrimination diagrams. The have high 87Sr/86Sr (0.704-0.707) and low 143Nd/ 144Nd (0.5124-0.5128). During their evolution, the magma was affected by crustal assimilation and fractional crystallization (AFC). Nd and Sr isotopic compositions support an origin of derivation by combined continental crustal AFC from a basaltic parent magma. A slab breakoff model is consistent with the evolution of South Marmara Sea granitoids.
Original language | English |
---|---|
Pages (from-to) | 1181-1200 |
Number of pages | 20 |
Journal | International Journal of Earth Sciences |
Volume | 97 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2008 |
Funding
Acknowledgments We acknowledge the Scientific and Technical Research Council of Turkey (TUBITAK: project code YDABC¸ AG-101Y007) for supporting the field study and geochemical analyses. Z. Karacık also thanks Ö.F. Gürer for help during the fieldwork. Dr. Judith Bunbury and anonymous reviewer provided very constructive comments on the manuscript.
Funders | Funder number |
---|---|
TUBITAK | AG-101Y007 |
Türkiye Bilimsel ve Teknolojik Araştirma Kurumu |
Keywords
- Assimilation fractional crystallization (AFC)
- Geochemistry
- Granitoids
- Slab breakoff
- South Marmara region