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估算原始地幔的组成,被普遍认可并采用的是Jaguotz等提出的模式,该模式利用Mg-Al-Si“空间”内地球演化趋势和宇宙演化趋势相交于原始地幔组成,从而获得原始地幔的Mg/Si比值,进而推算出其它元素组成。但是由于①在核幔分异过程中部分Si可能进入地核,从而可能影响Mg/Si比值;②对Jaguotz模型的改进用到了微量元素Nd,由于微量元素易受后期交代作用的影响,选用微量元素指标又给样品的挑选增加了难度,同时也增加了人为因素对结果的影响。为此本文对Jagoutz的方法作了改进,利用Mg/Al值代替Mg/Si值,以消除由Si进入地核而产生的影响。在此基础上推算了江苏六合地区原始
Estimating the composition of the original mantle is generally accepted and adopted by the Jaguotz et al. Model, which uses the evolution of the Earth and the evolution of the universe in the Mg-Al-Si “space” to intersect with the original mantle to obtain the Mg of the original mantle / Si ratio, and then calculate the other elements. However, since some Si may enter the core during the differentiation process of the mantle, which may affect the Mg / Si ratio. ② The improvement of the Jaguotz model uses the trace element Nd. Since the trace elements are susceptible to the effect of later metasomatism, Elemental indicators in turn give the sample more difficult to select, but also increased the impact of human factors on the results. In this paper, the method of Jagoutz is improved, and the effect of Si entering the nucleus is eliminated by using Mg / Al instead of Mg / Si. On this basis, the original counties in Liuhe area of Jiangsu Province are calculated