undatable

与undatable相关的网络例句 [注：此内容来源于网络，仅供参考]

Assuming that variations of the marine 13C/12C ratio are directly recorded in carbonate rocks, thousands of carbon isotope analyses of late Precambrian examples have been published to correlate these otherwise undatable strata and to document perturbations to the carbon cycle just before the great expansion of metazoan life.

新元古代较低的13C/12C比值被认为是前寒武纪特有的变化，这些变化包括所有有机质在海洋中的完全氧化以及生物产率的下降导致的热液二氧化碳的输入。通常热液中的二氧化碳被认为拥有较低的13C/12C比值。