MID-TO LATE-HOLOCENE SEA LEVEL HIGHSTANDS: EVIDENCE FROM FRINGING CORAL REEFS AT QIONGHAI, HAINAN ISLAND

Systematic field investigation and elevation survey were carried out on emerged primary dead massive corals and sub-tidal living micro-atolls along the coast of Qingge Township, Qionghai City, Hainan Island. Samples collected from these dead massive corals were also dated by the high-precise TIMS Useries method. The results show that:(1)micro-atolls on the outer reef flat at Qingge are precise sea-level indicators because their surface elevations are confined in a narrow range of only 8 cm below the lowest tidal level; (2) paleo-sea-level, indicated by the elevations (as relative to the mean elevation of living micro-atolls) and U/Th ages of primary dead corals, was at least 1 m higher than the present one during the stage 5 500-5 200 years ago, or more likely to be 2.0-2.2 m above the present; (3) paleo-sea-level, which oscillated by up to 0.6 m during the period of 5 500-3 500 aBP, was coincident with climatic changes on the whole; (4) the conspicuous lack of coral growth 4 400-3 900 aBP correlates well with the cold and dry period in south China reflected in speleothem δ¹⁸0 records from Dongge Cave in Guizhou Province, which coincides with the collapse of the Neolithic Culture of China (NCC).