The geochemistry of redox sensitive trace metals
The geochemistry of redox sensitive trace metals
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氧化还原敏感痕量金属的地球化学
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
J. Morford
中科院分区：
文献类型：
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作者：
J. Morford
沉积物中 V、Mo、Cd、U 和 Re 对不同氧化还原条件的富集/消耗特征凸显了它们作为古生产力和底层水氧浓度变化示踪剂的潜力。我们分析了西北非洲边缘、美国西北海岸和阿拉伯海的表层沉积物中的这些元素。图 1 绘制了来自非洲边缘和美国海岸每个岩心顶部 15 厘米的四个样品的金属分析结果。每种金属的自生行为取决于沉积物中还原条件的程度，而还原条件是由有机碳雨速率和底层水氧浓度决定的。非洲岩心（实心符号）具有经典的氧化还原趋势，其中两个较深岩心中孔隙水氧在深度 >2 厘米处降至零，并且 1) 或消耗 (<1) 被绘制为对数值，以适应金属自生的大范围。这些线代表在近岸沉积物生物扰动层下方观察到的值。由于深度再迁移而导致的表面沉积物中的表面锰、钼和钒富集不包括在内，因为它们仅被掩埋
The characteristic enrichment/depletion of V, Mo, Cd, U and Re in sediments in response to different redox conditions highlight their potential as tracers of changes in palaeoproductivity and bottom water oxygen concentration. We have analysed these elements in surface sediments from the Northwest African margin, the U.S. Northwest coast and the Arabian Sea. The results of metal analysis for four samples from the top 15 cm of each core from the African margin and the U.S. coast are plotted in Fig. 1. The authigenic behaviour of each of these metals depends on the extent of the reducing conditions in the sediments which is determined by the organic carbon rain rate and the bottom water oxygen concentration. The cores off Africa (closed symbols) have a classic redox trend in which pore water oxygen goes to zero at depths >2 cm in the two deeper cores and 1) or depletion (<1) are plotted as log values to accommodate the large range in metal authigenesis. The lines represent values observed below the bioturbated layer in nearshore sediments. Surface Mn, Mo and V enrichments in surface sediments due to remobilization from depth are not included because they are buried only