Geochemical and Lu-Hf Isotope Systematic of Detrital Zircons from the Ordovician Sandstones of the Sol-Iletsk Arch (Russia, Northern Caspian, Borehole Ordovician-2)

Abstract

The Sol-Iletsk arch is located at the south eastern edge of the East European platform (EEP), where EEP adjoins with the Southern Urals. The results of the integrated (U-Pb age, Lu-Hf isotopic system and trace-elements) study of detrital zircons (dZr) from the Ordovician sandstones (within Sol-Iletsk arch) reached by borehole Ordovician-2 are presented. The primary sources of Early Precambrian dZr were most likely the crystalline complexes of the Late Proterozoic Volgo-Sarmatian and Taratash orogens and Archean Volga-Uralia basement. However, for numerous dZr with ages younger 1.65Ga, it is not possible presently to unambiguously identify primary sources. Crystalline complexes with such ages are absolutely atypical for the south-eastern part of the EEP, but they occurred within parts EEP very remote from Sol-Iletsk arch and beyond EEP.