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地幔的４０Ａｒ／３６Ａｒ比率含有重要的有关地球早期脱气程度的信息。许多研究者认为在亏损地幔，比如通过大洋中脊玄武岩（ＭＯＲＢ）采集的样品中４０Ａｒ／３６Ａｒ比率高达２８０００。然而，富集地幔中的４０Ａｒ／３６Ａｒ比率存在着激烈的争论。我们使用４Ｈｅ／４０Ａｒ－３６Ａｒ／４０Ａｒ和４Ｈｅ／４０Ａｒ－３Ｈｅ／４０Ａｒ图重新考察了ＭＯＲＢ和热点火山中Ｈｅ、Ａｒ惰性气体数据。在这些图中，两种组分之间的混合线出现直线，这使得我们比使用具有不同分母的图比如４０Ａｒ／３６Ａｒ－３Ｈｅ／４Ｈｅ图更容易解释相关数据，在４０Ａｒ／３６Ａｒ－３Ｈｅ／４Ｈｅ图中，所有的混合线以曲线的形式出现。可以得出结论：富集地幔中４０Ａｒ／３６Ａｒ比率比大气值高许多，可能比在热点火山中观测的最高值还要高。同时也提出：在ＭＯＲＢ中观测的高４Ｈｅ／４０Ａｒ比率源于部分熔融期间的动力不平衡
The 40Ar / 36Ar ratio of the mantle contains important information about the extent of early degassing on Earth. Many researchers believe that the 40Ar / 36Ar ratio is as high as 28,000 in samples collected in depleted mantle, such as through the mid-ocean ridge basalt (MORB). However, there is a heated debate about enrichment of the 40Ar / 36Ar ratio in the mantle. We re-examined the He and Ar inert gas data for MORB and hotspot volcanoes using 4He / 40Ar-36Ar / 40Ar and 4He / 40Ar-3He / 40Ar maps. In these figures, a straight line appears in the mixed line between the two components, which makes it easier to interpret the data than using graphs with different denominators such as the 40Ar / 36Ar-3He / 4He diagram. In 40Ar / 36Ar-3He / 4He In the figure, all mixed lines appear as curves. It can be concluded that the 40Ar / 36Ar ratio in enriched mantle is much higher than the atmospheric value, perhaps higher than the highest value observed in the hot volcano. It is also proposed that the high 4He / 40Ar ratio observed in MORB originates from a kinetic imbalance during partial melting