兰州地区古气候变化的奇怪吸引子研究

Study on Strange Attractors of Palaeoclimatic Variations since 1 4 Ma B.P. in Lanzhou Region

利用兰州九洲台黄土剖面磁化率资料分析了古气候变化的混沌特性．结果表明，该地区１．４Ｍａ以来的古气候是具有有限个自由度的复杂系统，吸引子的关联维数为４．３。

The nonlinear characteristics of palaeoclimatic variations of Lanzhou have been studied in this paper by using the chaotic method. The time series is 1 4 Ma, while the time interval is 500 years with 2 801 sample points. The calculated results show the palaeoclmatic evolution in Lanzhou is a complex chaotic system with finite degrees of freedom. The association embedded dimension attractor is 4 3, while the saturation dimension is 12.