(Table 2) Trace element contents in ancient Black Sea sapropelic muds@en

The study of vertical distribution of Mo, V, Co, Ni, and Cu in mass of Black Sea sediments showed that maximum concentrations occur in sapropelic muds of ancient Black Sea deposits. A special study of sapropels samples showed a sufficiently clear correlation of Cu, Ni, Mo, and V contents with organic carbon contents; Co contents do not show such a correlation, but show one with contents of pyrite sulfur. A study of fractions of bitumen, free humic and fulvic acids showed that some part of metal contents in the sediments is bound with organic matter. It is shown that increased concentrations of trace elements in sapropels result from removing of dissolved metals from seawater by organic detritus during deposition on the bottom, in vivo concentration of metals in plankton organisms is of secondary importance.对黑海沉积物中钼（Mo）、钒（V）、钴（Co）、镍（Ni）及铜（Cu）的垂向分布研究表明，其浓度峰值均赋存于古黑海沉积的腐泥质泥层中。针对腐泥样品的专项研究显示，铜、镍、钼与钒的含量与有机碳含量存在显著相关关系；钴的含量则未呈现此类相关性，却与黄铁矿硫含量存在关联。通过对沥青、游离腐殖酸与富里酸分级组分的分析发现，沉积物中的部分金属元素与有机质形成结合态。研究证实，腐泥中微量元素浓度升高的成因是海底沉积过程中有机碎屑从海水中吸附溶解态金属，而浮游生物体内的金属富集仅处于次要地位。