E.A. SADIKHOV (VSEGEI), A.A. VELIEV, A.A. BAIRAMOV, S.M. MAMEDOV, D.R. IBRAGIMOV (Azerbaijan International Mining Company Limited)

Isotope geochemical characteristics (Sm-­Nd, Rb-­Sr, S) and U-­Pb SHRIMP II the age of the Gedabek intrusive (Azerbaijan)

The Gadabek intrusion is one of the largest porphyry copper and Au-­Ag epithermal deposits in Azerbaijan, for which are presented the latest isotope­geochemical studies, including zircon dating (U­-Pb SHRIMP II), the definition of ¹⁴⁷Sm /¹⁴³Nd, ⁸⁷Rb/⁸⁶Sr ratios, as well as stable isotopes of S. Interpretation of the formation of sulfide minerals based on sulfur isotopes, which showed that the sulfur in the fluid had reduction condition and a dominant hydrosulfide form. The rocks show typical subduction­related magmatism. They are enriched in large­ion lithophilic elements: K, Rb, Ba and U, Th. The prevalence of LREE over HREE, negative Ta-­Nb anomaly and positive Pb. All samples are characterized by low ⁸⁷Sr/⁸⁶Sr, relatively high ¹⁴⁴Nd/¹⁴³Nd ratios and positive values of ε_Nd=+5…+6. On the basis of geochemical and isotope­-geochemical data, argues that the possible mantle source occurred from mantle edge with an age of crystallization of 144 Ma (Early Cretaceous, Berriasian stage).
Keywords: U-­Pb age, Lesser Caucasus, isotope geochemistry.