orogenic event
1.The evidence of major and trace elements (including REE) as well as Sm Nd isotope of the rocks shows that there existed an early or earlier than Palaeoproterozic crust in western Hainan, and that the Baoban Group metasedimentary rocks partly originated from antiquity crust materials, and partly from new born crust with more mantle volcanic materials or was related with the largescale orogenic event and the tectonic magmatic activity following the addition of mantle materials.
