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Determination of the concentrations of. 15 rare earth elements (REE) in China continental shelf sediments by X- ray fluorescent spectral analysis of selected representative sediment samples showed that REE concentration in the sediments is 156 ppm, similar to that in China loess and Fujian granite, but different from that in Pacific sediments. The shelf REE have the characteristic distribution pattern of typical continental crust REE and evidently philo-continental property. The above findings suggest that weathered materials transported from the China continent are the main source of the REE in China continental shelf sediments.Experiments show that REE exist mainly in the crystal lattices of clay minerals ( <2u) as isomorphs and that REE have close relation with most elements (Al, Ti, K, Rb, Fe, etc.) related with clay minerals, but have negative correlation with the biophile elements Ca and Sr. 相似文献
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东海大陆架海底沉积物稀土元素地球化学研究 总被引:27,自引:4,他引:27
REE geochemistry has been studied with respect to sea-floor sediments in the continental shelf of East China Sea. The average content of RE2O3 is derived as 175 ppm based on 68 samples of the continental Y and La-Lu in the abovementioned shelf sediments, The absolute concentrations of sediments are shown in Table 3. The REE distribution patterns of the sediments demonstrate a distinct depletion in Eu and a negative slope. It is considered that the fragments of Mesozoic intermediate-acid igneous rocks widely distributed in southeastern China are the main souree of REE in sea-floor sediments of the continental shelf. 相似文献
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阿尔泰三号伟晶岩脉岩浆演化过程中铌,钽示踪的研究 总被引:2,自引:2,他引:2
对三号伟晶岩脉某些不相容元素的分异与演化进行了研究,结果表明,岩浆作用中不相容元素Nb,Ta的不相容性在花岗伟晶岩浆演化过程中已大大减弱,Nt,Ta,独立矿物如铌钽铁矿,细晶石等形成于伟晶质熔体的各个演化阶段,依据地质观察和分析数据对三号伟晶岩脉的分离结晶过程进行恢复,同时,计算了Nb,Ta在熔体与白云母,微斜长石,钠长石,锂辉石等主要矿物之间的分配系数,对Nb,Ta的成矿作用也进行了讨论。 相似文献
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东海沉积物的稀土和微量元素 总被引:14,自引:3,他引:14
本文对东海沉积物稀土和某些微量元素的地球化学特征进行了系统的讨论,研究结果表明,东海陆架区沉积物的稀土和微量元素含量随样品的粒度由粗到细呈规律性变化。唯冲绳海槽区沉积物的稀土元素含量例外,具体表现为海槽西坡到东坡,随沉积物粒度由粗→细→粗,稀土元素含量因受沉积物矿物成分控制而逐渐降低。东海沉积物的稀土元素分布模式类似页岩,表明其物质来源主体仍是陆源的。 相似文献