(Table 1) 3He/4He and 4He/20Ne ratios of pore gases in sediment at DSDP Sites 84-568 and 90-594

Studies on He isotope ratios of gas and rock samples in various parts of the world have shown a close relation between the 3He/4He ratio and geotectonic features of the sampling area. Emission of primordial He is commonly found in gases and fluid in Cenozoic volcanic areas (mid-ocean ridges, hot spots, and subduction zones), whereas that of radiogenic He is predominant in continental areas. Thus, the 3He/4He ratio is considered a useful tool for evaluating a variety of geotectonic environments.

针对全球各地气体与岩石样品的氦同位素比值所开展的研究表明，3He/4He比值与采样区域的大地构造特征存在紧密关联。原始氦的释放常见于新生代火山活动区（洋中脊、热点及俯冲带）的气体与流体中，而放射成因氦则在大陆区域占主导地位。因此，3He/4He比值被视作评估多种大地构造环境的有效工具。