THE GEOCHEMISTRY AND TECTONIC SETTING OF THE DEMIRKOY PLUTON OF THE SREDNOGORIE-ISTRANCA GRANITOID CHAIN, NW TURKEY


AYKOL A., TOKEL S.

MINERALOGICAL MAGAZINE, cilt.55, ss.249-256, 1991 (SCI İndekslerine Giren Dergi) identifier

  • Cilt numarası: 55 Konu: 379
  • Basım Tarihi: 1991
  • Doi Numarası: 10.1180/minmag.1991.055.379.13
  • Dergi Adı: MINERALOGICAL MAGAZINE
  • Sayfa Sayıları: ss.249-256

Özet

The chain of Late Subhercynian granitoids can be traced along the Srednogorie-Istranca-Pontid belt. The Demirkoy pluton outcrops in the Istranca segment. The rocks of the pluton range from diorite through grandiorite to perthite granite with granodiorite predominating. On the basis of 25 chemical analyses, the intrusive setting of the granitoid has been investigated. Calcic to calc-alkaline and peraluminous to metaluminous character indicate a subduction-related origin. Low to moderate concentrations of the large-ion lithophiles (LIL), high field strength elements (HFS), light rare earth elements (La, Ce) and low HFS/LIL ratios indicate a mantle-derived magma with subduction-related enrichment. Trace element discrimination diagrams such as Rb/Zr-Nb, Rb/Zr-Y, Rb-SiO2 and Rb-(Nb + Y), are particularly indicative of normal arc-setting for the samples.