Planktonic foraminifera and sea surface temperature (SST) of the Xisha Trough, South China Sea since Last Glaciation

South China Sea is the largest marginal sea of the Western Pacific between the Pacific Ocean and Asia Continent. It has been influenced by both the Pacific Ocean and continental climate. Its continental margins are broad in north and south, narrow in west. There are many islands in east. A large amount of siliciclastic sediments derived from peri-continents and islands were trans-ported into the sea1], in which significant information of paleoceanography and paleoclimate and paleoenvironm…

Planktonic foraminifera and sea surface temperature (SST) of the Xisha Trough, South China Sea since Last Glaciation

The high-resolution analysis on the carbon and oxygen isotopes and planktonic foraminifera of core SA12-19 dated with 14C approach in the Xisha Trough of South China Sea indicates that sediments are attributed to oxygen isotope stages 1-3 (stage 3 is not included completely), during the late-glacial to post-glacial periods. The sea surface temperature (SST) of each sample is calculated based on palaeoecological transfer functions (FP-12E). The results reveal a gradual thermocline increase in this area during oxygen isotope stages 1-3 e.g. a temporal thermocline deepening in the middle Holocene. During the Holocene, the SST was 23.3-27.2℃ in winter, 28.8-29.8℃ in summer. During oxygen isotope stage 2, the SST was 21.4-24.4℃ in winter, 28.1-29.0℃ in summer; and 21.9-25.2℃ in winter, 28.5-29.3℃ in summer during oxygen isotope stage 3. The SST in winter during oxygen isotope stage 2 was 2-6℃ lower than that of stage 3. During the transitional period, a "Younger Dryas Event", standing for a rapid climate return, occurred obviously.