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研究样品于1988年采自太平洋东部CC48孔。通过对沉积物稀土元素地球化学特征的分析发现：（1）各种类型深海沉积物的稀土含量有所差别，以稀土元素总量（ζREE）而论，深海粘土＞硅质软泥＞硅钙质轨泥＞钙质轨泥Z沉积物中的自生矿物、谁质生物成因的非晶质SiO2及碎屑矿物对稀土元素起富集作用，而生物CaCO3则起分散作用。（2）稀土元素含量随深度发生变化，为地层划分提供了依据，应用元素地层学方法将岩芯分成5个层段。（3）据稀土元素分异特征区分出3种沉积环境（CCD之上、CCD之下和过渡型），而［La／Ce］sh比值的变化，表明早中新世温度、南极底层流及氧化还原条件经历了3个变化旋回。
The study sample was collected from the CC48 hole in the eastern Pacific Ocean in 1988. Through the analysis of geochemical characteristics of rare earth elements in the sediments, it is found that: (1) The contents of REEs in various types of deep-sea sediments are different. In terms of the total REE (ζREE), deep-sea clays> siliceous slime> Mass track mud> calcareous orbit Z sediments in the authigenic minerals, who host biological causes of amorphous SiO2 and detrital minerals from the enrichment of rare earth elements, and biological CaCO3 play a dispersion. (2) The content of REE changes with the depth, which provides the basis for stratigraphic division. The element core is divided into 5 layers using elemental stratigraphy method. (3) The variation of [La / Ce] sh ratio in three sedimentary environments (above CCD, under CCD and transitional type) is distinguished according to the characteristics of REE differentiation. It shows that the temperature of Early Miocene, Redox conditions have undergone three cycles of change.