Geochronology, geochemistry and its tectonic significance of Chahe granites in Hainan Island

Abstract

There are very few studies on the granites formed in Late Permian in Hainan (海南) Island. Petrology, geochronology and geochemistry research on Late Permian granites in Chahe (叉河) area, Hainan Island will be reported in this article. The results show that, Chahe granites formed in 251 Ma, are riched in SiO₂, alkali, Fe₂O₃ while depleted in MgO and CaO, with low Sr and high Yb, and have all the features consistent with A-type granite. The forming of Chahe granites may suggest that Hainan Island was already in post-orogenic setting in Late Permian.

Keywords

granite / U-Pb age dating / geochemistry / Hainan Island

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