Hercynian And Indosinian Structureal Overprinting And ～(40)Ar-～(39)Ar Geochronology Of Hainan Island-South China

Hainan Island lies in the junction of Eurasian Plate, India-Australia Plate and Philippine Plate in geotectonics. It has very complicated history of geological structural evolution. Hainan Island is one of the key place to relate and understand the Mesozoic structural evlution of Indochina and southern China block. So, it has important science signification in understanding Mesozoic structural evlution of Hainan Island. This dissertation will systemic research the Hercynian and indosinan structure of Hainan Island by tectonics, petrology, petrography and ⁴⁰Ar-³⁹Ar chronology, and integrate predecessor's studies on Hercynian and indosinan structure deformation and deformation chronology researchs both of Song Ma region in north Indochina peninsula and inner southern China block, discuss the tectonic evolution and mechanism of Hainan Island.The first stage structure deformation (D₁) formed in Jinningian. Baoban group, the oldest basement in south Hainan Island, had been folded and uplifted. There has no Neoproterozoic in south Hainan Island. But, in north Hainan Island, there exist angular unconformitys between Mesoproterozoic Baoban group and Neoproterozoic Shilu group and between Neoproterozoic Shilu group and Sinian Shihuiding formation. Baoban group and Shilu group had been folded and uplifted. It had magma activity. The second stage structure deformation (D₂) formed in Caledonian. In south Hainan Island, the mid-late Cambrian was lacunal, early Paleozoic and the older stratum had been folded and uplifted. There exist regional angular unconformity between early Paleozoic and late Paleozoic in north Hainnan Island. The Eopaleozoic stratum had been folded and uplifted, and fold belts/faulted zones be formed. It had general metamorphism and...