Collision with Gondwana or with Baltica? Ordovician magmatic arc volcanism in the Marmarosh Massif (Eastern Carpathians, Ukraine).

ABSTRACT: The pre-Alpine Marmarosh Massif is a tectonically complex unit of the crystalline basement within the Eastern Outer Carpathians. In the eastern (Ukrainian) segment of this massif, two units have been identified-the Bilyi Potok Nappe and the Dilove Nappe. Petrological investigations coupled with zircon U-Pb dating were performed on metavolcanic rocks (porphyroids) and their phyllite host rocks, sampled from three locations within the Dilove Nappe. The geochemical characteristics of the meta-rhyodacite porphyroids revealed a volcanic arc affinity of the protolith, with U-Pb zircon ages of 452.8 ± 1.5 Ma and 461.5 ± 1.6 Ma and zircon saturation temperatures in the range of 823-892 °C. The phyllite host rocks (meta-tuff) yield a U-Pb zircon maximum estimate for the eruption age at 584.7 ± 2.9 

SUBMITTER: Gaweda A 

PROVIDER: S-EPMC9464182 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature