鹤壁地区石炭-二叠系稀土元素地球化学特征

Geochemical Characteristics of REE in the Permo-Carboniferous System in Hebi Area

采集了鹤壁地区石炭-二叠系岩石样品,采用电感耦合等离子质谱技术对样品进行了系统的稀土元素测试分析。测试样品稀土总量平均值为102.88μg/g,明显低于北美页岩组合样,灰岩样品∑REE较低,粉砂岩∑REE最高;样品δEu为0.45-0.75,平均0.63,明显Eu负异常;δCe为0.53-1.11,平均为0.84;稀土配分模式总体为轻稀土富集、重稀土亏损;灰岩中Ce的负异常指示了古海水为氧化环境,Eu异常反映母岩类型为花岗岩。

The rock samples of the Permo-Carboniferous system in Hebi Area were collected and an ICP-MS method was used to analyze the rare earth elements of the samples systematically.The average of total REE amount in sample tested is 102.88 μg/g,and it is obviously lower than the North American shale samples,the total amount of REE in the limestone is lower and in siltstone is max.The δEu is 0.45～0.75,and the average is 0.63,and the samples are lack of Eu;the δCe is 0.53～1.11,and the average is 0.84.The rare earth element patterns indicate that the LREE is rich and the HREE is lack. The lack of Ce in limestone indicates that the ancient seawater was in oxidizing environment,and the abnormal δEu reflects the type of matrix is granite.