کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4726866 1640146 2011 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Forearc serpentinite mélange from the Hongseong suture, South Korea
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
پیش نمایش صفحه اول مقاله
Forearc serpentinite mélange from the Hongseong suture, South Korea
چکیده انگلیسی

The signature of a prolonged subduction–accretion history from Paleozoic to Early Mesozoic is preserved within the dismembered serpentinite mélanges within the Hongseong suture. Here we present major and trace element data from the mafic fragments/blocks within the Baekdong serpentinite mélange revealing their arc-like tholeiite affinity within a suprasubduction zone tectonic setting. Chromian spinel compositions from the Baekdong hydrated mantle peridotite (serpentinite) are characterized by high Cr# (0.53–0.67) and Fe2+/Fe3+ ratio, medium Mg# (0.42–0.55), and Al2O3 contents (17–25 wt.%) indicating a forearc tectonic environment for the hydrated mantle peridotite. The estimated melting degree (> 17.6%) and FeO/MgO of the parental melt (0.9–1.3) are consistent with that of forearc magmas. SHRIMP zircon U–Pb ages from a high-grade mafic rock and an anorthosite from the study area give protolith ages of ~ 310 Ma and ~ 228 Ma, respectively. Zircons from an associated orthogneiss block within the mélange yield a Neoproterozoic crystallization age of ~ 748 Ma. These results, together with the recent SHRIMP zircon ages from other dismembered serpentinite mélanges within the Wolhyeonri complex, suggest that Paleozoic to Early Mesozoic subduction and subsequent collision events led to the exhumation of the hydrated forearc mantle peridotites from a metasomatized mantle wedge. The Hongseong region preserves important clues to a long-lived subduction system related to global events associated with the final amalgamation of the Pangaea supercontinent.

Figure optionsDownload as PowerPoint slideResearch Highlights
► Exotic blocks of arc tholeiite basalt/gabbro and anorthosite within the serpentinite mélange.
► Forearc tectonic environment for the hydrated mantle peridotite.
► Paleozoic to Early Mesozoic subduction and subsequent collision led to the exhumation of the hydrated forearc mantle peridotites from a metasomatized mantle wedge.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Gondwana Research - Volume 20, Issue 4, November 2011, Pages 852–864
نویسندگان
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