Traces of intra-oceanic arcs recorded in sandstones of eastern Kazakhstan: implications from U–Pb detrital zircon ages, geochemistry, and Nd–Hf isotopes

Inna Safonova, Alina Perfilova, Olga Obut, Pavel Kotler, Shogo Aoki, Tsuyoshi Komiya, Bo Wang, Min Sun

Результат исследования: Научные публикации в периодических изданияхстатьярецензирование

Аннотация

This paper presents first U–Pb detrital zircon ages, major and trace element geochemical data and whole-rock Nd and Hf-in-zircon isotope data from sandstones of the Char and Zharma zones of eastern Kazakhstan. Petrographically the sandstones represent greywackes. The U–Pb ages of detrital zircons show unimodal distributions peaked at 345–340 and 330–325 Ma indicating post-Early Carboniferous deposition. The sandstones have high CIA values (60–68), suggesting moderate to weak chemical weathering. Their high ICV values (1.1–1.3) and relatively high MgO and low Y, Nb indicate an immature probably mafic–intermediate igneous source (low La/Th, medium Hf). Positive whole-rock εNd(t) and zircon εHf(t) indicate dominantly juvenile character of igneous rocks in the provenance. In total, the unimodal character of U–Pb detrital zircon age patterns, the chemical composition of sandstones similar to that of associated volcanic rocks and the positive values of εNd(t) and εHf(t) suggest their derivation from one or more intra-oceanic arcs. The data from eastern Kazakhstan fit those obtained from late Paleozoic greywacke sandstones of NW China. The new geochemical and geochronological data from sandstones and published data from oceanic and supra-subduction ophiolites of eastern Kazakhstan suggest an extended Pacific-type subduction system in the western Paleo-Asian Ocean in Devonian–early Carboniferous time.

Язык оригиналаанглийский
ЖурналInternational Journal of Earth Sciences
DOI
СостояниеОпубликовано - 19 июн 2021

Предметные области OECD FOS+WOS

  • 1.05 НАУКИ О ЗЕМЛЕ И СМЕЖНЫЕ ЭКОЛОГИЧЕСКИЕ НАУКИ
  • 1.05.KY ГЕОЛОГИЯ

Fingerprint

Подробные сведения о темах исследования «Traces of intra-oceanic arcs recorded in sandstones of eastern Kazakhstan: implications from U–Pb detrital zircon ages, geochemistry, and Nd–Hf isotopes». Вместе они формируют уникальный семантический отпечаток (fingerprint).

Цитировать