南海北部沉积物磁化率对古气候非线性变化的响应

对南海北部海区ＳＯ－５０－２９ＫＬ柱样全孔磁化率与古气候变化作对比研究，结果表明：（１）沉积物磁化率较好地响应着古气候的变化，存在明显的地球轨道偏心率、岁差及岁差半周期，（２）奇异谱分析结果显示十余万年来磁化率曲线的统计维为９，与黄土获得的结果基本一致．各主成分变化的周期均与增分析所得的周期大致吻合；（３）奇异谱分析所得的各成分的变化特征显示了过去十余万年古气候存在明显的非线性变化。

A RESPONSE TO PALEOCLIMATIC NONLINEAR VARIATIONS FROM SEDIMENT MAGNETIC SUSCEPTIBILITY IN NORTHERN SOUTH CHINA SEA

Spectrum Analysis and Singular Spectrum Analysis (SSA) are adopted to compare the sediment magnetic susceptibility from core SO-50-29KL with paleoclimatic variations, which results show: (1) Sediment magnetic susceptibility is corresponding well to paleoclimatic variation, the Milankovitch cycles (eccentricity, precession and semiprecession) are well detected; (2) That the application of SEA method to investigate the nonlinear dynamic characteristics shows the statistical dimension is 9, which is similar to the result from loess. The principal components of SSA correspond well to the Milankovitch cycles; (3) Nonlinear variations of the paleoclimate are found throughout depositing time of the core.