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总共224个陆源海相沉积和远洋沉积样品采自小浜(Dbama)海湾、骏河(Suruga)海湾、纪伊(Kii)海峡南部、东北日本沿海、日本海沟(为陆源海相沉积)和中太平洋(为远洋沉积)。经溶解萃取分离后,在石墨炉雾化器中使用原子吸收分光仪对样品中的金进行分析。金的平均含量在陆源沉积中为(2.4±1.2)×10-9(样品数n为85),在远洋沉积中为(1.4±1.3)×10-9(样品数n为139),这与金在地壳中的丰度相似。在陆源沉积中金与铜呈显著正相关(r=0.82),而在远洋沉积中则无此趋向。已知在金矿化地区沉积物中存在高的Au/Cu比值,因而,Au/Cu比值可以作为金矿床地球化学勘探的有用指标。关于金和有机碳在远洋沉积中的含量,表层样品有较高的数值,而在较深的沉积物中却未见踪迹。在陆源沉积中金和有机碳却无这样的垂向富集趋向。金在远洋沉积中的这种垂向富集现象被认为是在早期成岩作用中,含金有机金属络合物向上迁移的结果。而在陆源沉积物中,金最可能的存在形式是原子状态,因此,在成岩过程中无明显迁移,缺少垂向富集趋向。
A total of 224 terrestrial marine and ocean sediment samples were collected from Dbama Bay, Suruga Bay, southern Kii Strait, northeastern Japan Coast, Japan Trench (for terrestrial marine sediments) and the Central Pacific Ocean (For ocean sediments). After dissolution extraction, the gold in the sample was analyzed using an atomic absorption spectrometer in a graphite furnace atomizer. The average gold content was (2.4 ± 1.2) × 10-9 (n = 85) in terrestrial sediments and (1.4 ± 1.3) × 10-9 in ocean sediments The number n is 139), which is similar to the abundance of gold in the crust. There was a significant positive correlation between gold and copper in terrigenous sediments (r = 0.82), but no such trend in ocean sediments. It is known that there is a high Au / Cu ratio in the sediments in the gold mineralization area. Therefore, the Au / Cu ratio can be used as a useful index for geochemical exploration of gold deposits. As for the content of gold and organic carbon in the oceanic sediments, the surface samples have higher values but no trace in the deeper sediments. There is no such tendency for vertical enrichment of gold and organic carbon in terrigenous sediments. This vertical enrichment of gold in ocean sediments is thought to be the result of upward migration of gold-bearing organometallic complexes during early diagenesis. In the terrestrial sediments, gold is most likely to exist in the atomic state, therefore, there is no obvious migration during diagenesis, and there is a lack of vertical enrichment tendency.