isotopic

The variations in isotopic ratios take place on the right time scale, and they mirror those seen in modern corals, he notes..他说，同位素比例变化所发生的时间范围恰到好处，这与在现代珊瑚中的发现保持了一致。

While initial research was aimed at looking at seasonal variations in diet, the isotopic tests pointed them instead to apparent gender variations..虽然初始的研究是为了确定其食物随季节的变化，同位素测试让他们发现了明显的性别差异。

Magma rising from deep within the Earth has a different isotopic and chemical composition than magma that forms just below Earth's crust..从地球深处所喷出的岩浆与仅低于地壳表面所形成的岩浆有着了不同的同位素和化学成分。

isotopic tracer,示踪同位素；同位素指示剂；示踪物