isotopic constitution meaning in English

同位素组成

3 . the correlation of isotopic constitution and the relations between diagenesis and co2 indicate that co2 mainly derived from tertiary ca - mud rocks . the carbonate cements in reservoirs under the affection of hot fluid may form co2 , but the yield of co2 is low
基于碳酸盐矿物及本区浅层co _ 2的同位素组成对比分析，并结合浅部储层成岩作用与co _ 2的相互关系，认为co _ 2可能来自第三系钙质泥岩。