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全球范围内的洋中脊玄武岩 (MORB)玻璃及气泡具有均一的CO2 /3He比率(CO2 摩尔数与3He摩尔数之比 ) ,为 ( 2～ 7)× 1 0 9,这表明通过洋中脊体系释放的幔源气体具有基本恒定的CO2 /3He比率。地幔脱气的机理研究表明 ,MORB中的该比率反映的是初始MORB岩浆的挥发份特征 ,而气泡在MORB岩浆中的成核、生长和上升的活动过程所造成的CO2 -3He的分离是很有限的 ,这说明幔源气体具有特征的CO2 /3He比率。匈牙利潘诺尼亚盆地等一系列的研究实例表明 ,幔源气体的CO2 /3He比率特征能够可靠地估计地幔脱气的通量 ,并为大陆地区构造拉张背景下的地幔脱气研究提供了一个可靠的约束条件。
Globally mid-ocean ridge basalts (MORB) glass and gas bubbles have a uniform CO2 / 3He ratio (CO2 moles to 3He moles ratio) of (2 to 7) × 1 0 9, indicating that the mid- The mantle-derived gas released by the system has a substantially constant CO2 / 3He ratio. The mechanism of degassing in the mantle shows that the ratio in MORB reflects the volatile characteristics of the initial MORB magma and the separation of CO2-3He caused by the nucleation, growth and ascending activity of bubbles in the MORB magma is very significant Limited, indicating that the mantle source gas has a characteristic CO2 / 3He ratio. A series of studies in the Panonian basin of Hungary have shown that the CO2 / 3He ratio of mantle source gases can reliably estimate the flux of the mantle degassing and provide a useful tool for studying the degassing of the mantle in the tectonic setting of the continental structure A reliable constraint.