神狐海域水合物沉积层稀土元素地球化学特征  

Rare earth elements geochemical characteristics of natural gas hydrates in Shenhu Area of the northern South China Sea

作　　者：王彦美[1,2] 韩冰[1] 吴能友[2] 赵明辉[3] 

机构地区：[1]广州海洋地质调查局,广东广州510760 [2]中国科学院可再生能源与天然气水合物重点实验室,中国科学院广州能源研究所,广东广州510640 [3]中国科学院边缘海地质重点实验室,中国科学院南海海洋研究所,广东广州510301

出　　处：《海洋学研究》2012年第3期35-43,共9页Journal of Marine Sciences

基　　金：中国科学院知识创新工程资助项目(KZCX2-YW-Q05-04);中国科学院可再生能源与天然气水合物重点实验室开放基金资助项目(0907k8);国土资源部中国地质调查局引进现代分析测试设备配套方法研究资助项目(1212010816025)

摘　　要：利用ICP-MS对神狐海域天然气水合物SHW2和SHW7两钻孔柱状样品含水合物层沉积物中的稀土元素进行了分析和研究,结果表明:SHW2及SHW7两钻孔各12个样品的ΣREE丰度平均值与上陆壳的平均值接近;沉积物中轻稀土和重稀土存在显著分异,两钻孔稀土元素配分模式相近,与上陆壳和代表上地壳平均值的澳大利亚后太古代页岩(PAAS)的稀土元素分布形态相似,并继承了源区母岩性质,显示出物源主体为陆源岩。两钻孔稀土参数剖面图显示,稀土总量(ΣREE)和轻稀土总量(LREE)、重稀土总量(HREE)具有很好的正相关性,δCe与δEu基本显示负相关,推测其沉积物源具有相似性。The REE geochemical characteristics bear much information about the provenance and sedimentary environment of natural gas hydrate. The REE contents and patterns of the sedimentary samples from stations SHW2 and SHW7 in Shenhu Area of the northern South China Sea were analyzed by ICP-MS. The results show that the average REE contents of samples from SHW2 and SHW7 are close to average REE content in upper continental crust. Analysis on LREE and HREE shows that there are significant fractionations in sediments. The REE patterns of two stations are similar. These characteristics are close to REE pattern in the upper continental crust and post-Archean Australian shale （PAAS）. It indicates that sediments of the hydrate area inherit characteristics of their provenance, which are mainly from terrigenous rocks. The profile charts of REE parameters of stations SHW2 and SHW7 show that there is much positive correlation among ЕREE, LREE and HREE, and there is negative correlation between δCe and δEu. It can be inferred that the sedimentary provenances of the two stations have similarity.

关 键 词：天然气水合物 稀土元素 地球化学特征 神狐海域 南海北部 

分 类 号：P736.4[天文地球—海洋地质]