南极普里兹湾NP951柱样元素地层与古环境初步研究

对南极普里兹湾ＮＰ９５１柱样的元素地球化学特征及其古环境意义进行了研究。结果表明，本区沉积物在沉积过程中受冰盖消融、淡水涌入和陆源物质的影响较大；沉积物中ＳｉＯ２、Ａｌ２Ｏ３、Ｆｅ２Ｏ３、ＣａＯ、ＭｇＯ、Ｐ、Ｓ、Ｃｏｒｇ等元素组分较好地记录了由古气候变化而引起的物源改变，这些元素组分在地层中的分布规律与古海洋沉积环境及古气候变迁相一致；自晚更新世末期以来的气候大致可分为温暖期、寒冷期、高温期、转冷期和转暖期五个区段；在柱样的１４５ｃｍ（１４．４ｋａＢ．Ｐ．）、８５ｃｍ（１０．３ｋａＢ．Ｐ．）和２５ｃｍ（６．３ｋａＢ．Ｐ．）处出现了古气温的高值点，指示了气候的变化；８５ｃｍ处元素含量的突变指示了异常事件的发生，该层位正好对应于哥德堡地球磁场漂移，全球气温突然变暖，标志着１０．３ｋａＢ．Ｐ．以后南极地区进入了全新世。

A PRELIMINARY STUDY ON THE ELEMENT STRATA AND PALAEOENVIRONMENT OF CORE NP95 FROM THE PRYDZ BAY,ANTARCTICA

This paper deals with the characteristics of element geochemistry of core NP951 from the Prydz Bay,Antarctica and its implications to palaeoenvironment. The results show that the sediments in this area were greatly affected by dissipation of ice cover,gush of freshwater and terrigenous materials in the process of deposition,and the elements such as SiO 2、Al 2O 3、Fe 2O 3、CaO、MgO、P、S、C org in sediments have well recorded the changes of material source resulted by variations of palaeoclimate and the distribution patterns of these elements correspond to the palaeosedimentary environment of ocean and the variations of palaeoclimate; The climate can be roughly divided into five periods such as warm,cold,high temperature,cold tendency and warm tendency since the late Epipleistocene; The turning points of temperature,which indicated the changes of climate,occurred at 145cm(14.4ka B.P.),85cm(10.3ka B.P.) and 25cm(6.3ka B.P.) of core NP951,and the sudden change of element content at 85cm of the core where corresponds to the Gothenburg geomagnetic excursion indicated occurrence of extremely event and marks the beginning of Holocene.