RECONSTRUCTION OF SEA SURFACE TEMPERATURE USING PLANKTONIC FORAMINIFERA FROM CORE MD06-3054 IN THE NORTHWESTERN PACIFIC

In paleoceanographic research,sea surface temperature (SST) is usually reconstructed with planktonic foraminifera.Results from different methods are diverse.In order to better understand the difference of these methods,the authors reconstructed the SST since the last glacial using the methods of transfer function FP12-E,Modern Analog Technique (MAT),and Mg/Ca ratios with samples from the core MD06-3054,which is located at the bifurcation of North Equatorial Current in the northwestern Pacific.The SST was recovered by counting planktonic foraminiferal fauna and measuring the Mg/Ca ratios of surface dweller Globigerinoides ruber (white,G.ruber in short).It is found that (1) the method of transfer function FP-12E is not applicative in this case; (2) the rising of SST from the last glacial to the post glacial stage reconstructed with MAT is smaller than that reconstructed from the Mg/Ca ratios in core MD06-3054; (3) take into consideration the production change of planktonic foraminifera tests with seasons,the increasing of the SST_Mg/Ca calculated from Mg/Ca ratios may larger than the changes in SST_A.Even so,comparing with the palaeoecological methods (such as MAT),the geochemical method of Mg/Ca ratios has fewer affecting factors and may provide more accurate data if calibration is made for seasonal productivity change of planktonic foraminifera.