摘要
用ICP-MS对取自Juan de Fuca洋脊Endeavour段5块热液硫化物样品的13个分析样进行了稀土元素(REE)测试。结果显示该区硫化物样品的REE含量较低(0.35～14.8μg/g),所有样品的REE球粒陨石标准化分布模式均表现出Eu正异常和LREE富集的特征,表明硫化物中的REE来自热液。不同喷口硫化物的REE含量变化较大,同一块状硫化物不同部位的含量也有较大差异,主要是由于硫化物形成过程中,热液和海水的混合不均一性以及不同矿物沉淀和(或)溶解的结果。硫化物REE的分布特征主要受热液的影响,烟囱内外层Eu正异常的变化主要受矿物组成和物理化学条件的控制。
Rare earth elements （REE） of 13 subsamples picked from 5 sulfide samples from the Endeavour segment, Juan de Fuca Ridge （JDFR） are analyzed by ICP-MS. The results show that contents of REE in samples are somewhat low （from 0. 35 to 14. 8 μg/g） and all of the chondrite-normalized REE patterns of samples are characterized by positive Eu anomalies and LREE enrichment. These indicate that REE in sulfides come from hydrothermal fluids. The contents of REE in sulfides from different vents vary obviously, and those in the same sulfide also have remarkable varieties. The discrepancies are due to the heterogeneities in the mixing of seawater and hydrothermal fluids and the dissolve and/or precipitation of minerals. The REE patterns of sulfides are controlled by hydrothermal fluids, moreover, the mineral assemblages and physico-chemical parameters in the inner and outer wall of the chimney play a role in the Eu anomalies.
出处
《地球化学》
CAS
CSCD
北大核心
2007年第3期303-310,共8页
Geochimica
基金
国家自然科学基金重点项目(40532011)
国家自然科学基金项目(40403004
40473032)
