地球磁场变化与古气候之间的关系，一直是国际上悬而未决的科学难题，同时晚更新世以来高分辨率的地球磁场变化过程，尤其是相对强度曲线的重建，国内在此方面的贡献比较稀少。申请者拟选择南海北部沉积连续、均质、稳定的数个钻孔，在详细岩石磁学研究基础之上，建立该海域晚更新世以来的相对地球磁场强度变化主曲线。挑选沉积速率较高的钻孔，高分辨率取样，重点恢复一些关键地磁极性漂移的结构特征和变化过程。同时，选择2-3个具有良好古气候信息的钻孔，挑选其中的袋拟抱球虫进行氧同位素和Mg/Ca比值研究，与相邻区域已有记录对比，获取独立的海水表层温度(SST)和海水氧同位素组成（冰盖体积）变化的信息。在此基础上，在具有同一尺度和精度控制的时间范围内，解析具有不同行为特征的一些关键古地磁极性漂移所发生的古气候背景，并分别应用连续小波变换等一系列数学分析方法，探讨地球磁场变化与区域古气候指标之间是否存在联系。

The correlation between geomagnetic variations and paleoclimate in the different time scales remains controversial since this issue was proposed. Meanwhile, Stacked relative paleointensity curves since the late Pleistocene are very scarce in China. In this application, a master relative paleointensity curve since the late Pleistocene will be constructed from the continuous, undisturbed and homogeneous sediments, which are constrained by the detailed rock magnetic results and radio-carbon dating in the northern South China Sea. Then, information of the independent sea surface temperature (SST) and the oxygen isotope components of sea water (the volume of ice sheet) will also be obtained from the Mg/Ca ratios and the oxygen isotope values of Planktonic Foraminifer, such as Globigerinoides Sacculifera selected from the core sediments,which can record good intensity information. Based on these works, some significant relative intensity lows and geomagnetic excursions will be firstly recovered and further studied to analysis the detailed structure and the corresponding paleoclimate context of these excursions.Specially, the in-phase or out-phase correlation between the excursions and climate events will be attentioned. A series of continous wavelet transform, cross spectra analysis and Hilbert-Huang transform for both the relative intensity and paleoclimate proxies will also be carried out to discuss whether there is critical relationship between paleomagnetic variations and the climate proxies (orbital parameters).