Deep sea pollen record during 12–1.6 Ma from the southern South China Sea and its response to environmental change

Abstract

Based on deep-sea pollen results (512–76 m) from ODP Site 1143 in the southern South China Sea (SCS), the climate and vegetation evolution sequence on the surrounding islands and the exposed continental shelf are discussed. The pollen records show that the pollen influx was quite low before 8.15 Ma and increased dramatically afterwards. The influx changes can be ascribed, on one side, to tectonics deformations around the southern SCS resulting in rapid uplift of islands and subsequent increase of the sediment rates and pollen influx and on the other side to climate cooling and monsoon enhancement. Around 2.63 Ma was another obvious boundary, the increasing of pollen and spores influx since this time was mainly related to global climate cooling. Spectrum analysis of pollen influx values shows that 2 Ma, 0.67 Ma, and 0.19–0.17 Ma cycles existed during 12–3.0 Ma, while 0.1 Ma and 46.9 ka cycles existed during 3.0–2.0 Ma.