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地幔中挥发份的分配及分布及其同位素组分可以确定地幔中发生的构造破坏活动。迄今许多研究者根据同位素组分研究地幔流体组成。其中最大的成就是地幔初始~3He 的发现。和测得金刚石的~3He /~4He 最大值为3.2×10~(-4),而空气的~3He ~4He 等于1.4×10~(-6)这个发现决定性地影响了地幔去气模式,并证实了地球深处至今还保存初始组分。另一方面很明显,在过去的地质时期中,由于构造活动,大部分挥发份在大气圈—海洋—沉积物—地壳—地幔系统内曾进行了再分配。假如地幔中曾有过初始组分,它可能与混入的组分相混合而失去自己原有的同位素标志。~3He /~4He 比值可能是未经受真正破坏而保存了原
The distribution and distribution of volatiles in the mantle and its isotopic composition can determine the tectonic sabotage activity in the mantle. To date, many researchers have studied the composition of mantle fluids based on isotopic composition. One of the biggest achievements is the discovery of the initial ~ 3He mantle. And the ~ 3He / ~ 4He maximum value of the diamond was 3.2 × 10 ~ (-4), while the ~ 3He ~ 4He of the air was equal to 1.4 × 10 ~ (-6). This discovery had a decisive effect on the pattern of mantle gas desorption Confirmed the depth of the Earth so far also save the initial components. On the other hand, it is clear that most of the volatiles were redistributed within the atmosphere-ocean-sediment-crust-mantle system during the past geologic period due to tectonic activity. If the initial component had been in the mantle, it could mix with the mixed components and lose its original isotopic signature. The ~ 3He / ~ 4He ratio may have been preserved without undergoing true damage