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南大西洋沉积物中多环芳香化合物的组成特征研究 总被引：1，自引：0，他引：1
10 samples of sediments obtained from the South Mid-Atlantic Ridge were measured for the abundances and distributions of polycyclic aromatic compounds(PAHs). The total concentrations of PAHs(∑PAHs) ranged from 2.768 to 9.826 μg/g dry sediment. The ∑PAHs was higher in sample 22V-TVG10 and sample 26V-TVG05 which were close to hydrothermal fields, with the lowest value in sample 22V-TVG14 which was farthest from hydrothermal fields, suggesting a probable hydrothermal origin of ∑PAHs of samples. Approximately nine kinds of PAHs were identified, and low molecular mass tricyclic and tetracyclic aromatic compounds were predominant in the samples. The concentrations of fluoranthene which were typical as hydrothermal alteration compounds were the highest among PAHs with dry weight between 0.913–3.157 μg/g. The phenanthrene homologue was most abundant in the samples, and the ratios between parent phenanthrene and methylphenanthrene which probably reflected the degree of hydrothermal alteration ranged from 0.097 to 1.602. The sample 22V-TVG10 possessing a maximum ratio value showed the intense influence of the hydrothermal alteration on this sample, which might further imply that PAHs in sediments were mainly derived from the hydrothermal alteration. 相似文献
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深海富REY泥中稀土元素赋存载体及其富集机制研究进展 总被引：1，自引：1，他引：0
综合前人发表的关于太平洋、大西洋以及印度洋等深海沉积物中稀土元素含量的数据,本文较为系统地阐述了全球深海富REY泥(REY-rich mud)的分布,分析了不同沉积环境下富REY泥中稀土元素的赋存载体及其控制因素,并进一步探讨了赋存载体中稀土元素的富集机制。研究发现深海富REY泥主要分布在太平洋和印度洋的深海盆地中,其中西北太平洋南鸟岛附近海域沉积物中稀土元素最为富集,是较为有利的稀土资源勘探潜力区。邻近热液区,深海沉积物中稀土元素含量受热液活动影响较大,稀土元素的主要赋存相是Fe-Mn水合(氢)氧化物,可能是热液流体扩散过程中,颗粒物中的Fe-Mn水合(氢)氧化物等吸附(scavenge)海水中的稀土元素所致。而在远离热液区的正常深海富REY泥中,高磷含量以及低沉积速率是导致其稀土含量相对较高的主要因素,赋存载体主要是生物成因磷灰石(鱼牙骨碎屑)。在磷灰石早期成岩阶段,海水和孔隙水中的REY进入磷灰石,在羟基磷灰石晶格中REE~(3+)与磷灰石中的Ca~(2+)发生类质同象替代:REE~(3+)+Na~+?2Ca~(2+)和REE~(3+)+Si~(4+)?Ca~(2+)+P~(5+),使其不断地富集稀土元素,但这还需要进一步研究。 相似文献
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