Metamorphosed mafic rocks with N-type MORB geochemical features in Hainan Island - Remnants of the Paleo-Tethys Oceanic Crust?

A number of metamorphosed mafic rocks occurred within the Paleozoic strata in the Chenxing and Bangxi regions at the northern side of the Changjiang-Q ionghai Fault in Central Hainan Island. These metamorphosed mafic rocks are tholeiites in chemistry. They are characterized by extreme depletion of Th , Nb, Ta and LREEs, resembling the depleted N-type mid-ocean ridge basalts (MORB). Field relations suggest that the protolith of the metamorphosed maf ic rocks were likely formed in Paleozoic, These metamorphosed mafic rocks w ith N-type MORB geochemical features were probably the remnants of the Pale o-Tethys oceanic crust.