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我国东部含油气盆地幔源CO2气藏的CO2／3He比率在107－1013之间，与幔源气体脱离玄武岩浆时恒定的CO2／3He比率（2×109～7×109）相比较发生了很大的变化。其中形成于中生代的万金塔CO2气藏，具有109～1013的高CO2／3He比率，而新生代以来形成的黄骅、济阳、苏北、三水等地的幔源CO2气藏，均以107－109的低CO2／3He比率为特征。研究表明，幔源气藏CO2／3He比率的形成受到了幔源气体的释放机制的控制。在玄武岩浆喷溢、侵入为幔源气藏的形成提供大量气源的同时，岩浆房中的幔源气体通过深切岩浆房的断裂通道直接释放，对幔源气藏的形成、幔源气体的补给以及气藏CO2／3He比率等地球化学特征的塑造具有重要作用。同时，我国东部含油气盆地中无机成因CO2气藏的CO2／3He比率特征为气藏的幔源成因提供了新的证据。
The CO2 / 3He ratios of the mantle source CO2 gas reservoirs in the eastern petroliferous basins are between 107 and 1013, compared with the constant CO2 / 3He ratio (2 × 109 to 7 × 109) when the mantle gas is released from basaltic magmas big change. Among them, the Wanjingta CO2 gas pool formed in the Mesozoic has a high CO2 / 3He ratio of 109-1013. The mantle-derived CO2 gas reservoirs in Huanghua, Jiyang, northern Jiangsu and Sanshui have formed since the Cenozoic A low CO2 / 3He ratio of 107-109 is characteristic. The research shows that the formation of CO2 / 3He ratio in the mantle source is controlled by the release mechanism of mantle gas. While basalt magma spurting and invaded provide a large number of gas sources for the formation of mantle source gas reservoirs, the mantle gas in the magma chamber was directly released through the fracture channel of the deep magma chamber, and the formation of the mantle source gas pool, Supply and gas reservoir CO2 / 3He ratio and other geochemical characteristics of the building has an important role. At the same time, the CO2 / 3He ratio of inorganic CO2 gas reservoirs in the oil-bearing basins in eastern China provides new evidences for the mantle origin of gas reservoirs.