Neogene oxygen isotopic stratigraphy,ODP Site 1148,northern South China Sea

A detailed stable isotopic study based on benthic foraminifera from 1165 samples of ODP Site 1148 (18°50.17.3’N, 116°33.93’E, water depth 3308.3 m), northern South China Sea, provides an excellent oxygen isotopic record with an average resolution of 30 ka. It contains the most continuous δ18O data with highest resolution for the whole Neogene sequence in the world. The　δ18O curve shows a step-like increasing upwards and records 5 increases, 3 decreases and 2 stable stages during the Neogene, reflecting the general trend of global cooling. Among these events theδ18O decrease at 17.2-14.5 Ma, and two δ18O increases at 14.5-13.6 and 3.0-2.4 Ma are most marked and globally comparable. The intervals at 13.6-10.2 and 6.0-3.0 Ma with the lowest-amplitude and least fluctuation in δO represent the most stable bottom water periods for the South China Sea.