stable tracer isotope

例句：

1. 1. Stable isotopes are used to study the Earth's crust and its composition.
   稳定同位素被用来研究地球的地壳及其组成。
2. 2.The research team found that the stable isotope ratios in the soil were consistent with those from previous studies.
   研究小组发现土壤中的稳定同位素比例与之前的研究所得一致。
3. 3. The stable isotope data has been used to estimate the age of the rocks.
   稳定的同位素数据被用来估算岩石的年龄。