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分析了中国东部8个地区59件新生代地幔岩包体的金含量,并分析了相应地区85件地幔岩硫化物相的金含量,结合文献共报道了130件硫化物相的金含量.将两种金含量进行比较,发现地幔岩包体全岩金含量通常为10-9～10-8,而一些地幔岩包体硫化物中Au含量可达10-4～10-2,是全岩的数十万倍,证实地幔岩中Au主要赋存于地幔硫化物相中.将两种金含量分布进行比较,发现空间上地幔岩包体全岩和地幔岩包体硫化物相中金含量分布都是不均一的,但二者金含量分布变化规律相一致,即地幔岩包体中Au含量高的地区,地幔岩包体硫化物相中金含量也高.除海南岛外,位于华北地台南北缘的山东临朐、昌乐和河北汉诺坝地幔岩包体全岩和包体硫化物相中金含量分布均较高,与冀北西部和山东胶东半岛的金矿集中区有对应关系,反映地幔的高金含量可能为相应地区金矿的形成提供了物质基础.古老的华北地台原始地幔曾有富金的物质基础,经后期地幔事件后仍富金,说明后期地幔事件(如减薄、去根、底侵、拆沉、置换、交代等)及有关的富CO2含金地幔流体对金活化、富集和转移直到成矿作用是在先期岩石圈地幔的物质基础上发生的.
The gold content of 59 mantle plunges in eight areas of eastern China was analyzed, and the gold content of the sulfide mantle in 85 mantle rocks in the corresponding area was analyzed. The gold content of 130 sulfide phases was reported in the literature The comparison between the two gold contents shows that the gold content of the mantle lithofacies is generally 10-9 ~ 10-8, while the Au content of some mantle lithospergite reaches 10-4 ~ 10-2, Several hundred thousand times that of the mantle rock, confirming that Au in the mantle rock mainly exists in the mantle sulphide phase.Comparing the two gold content distributions, it is found that the gold content in the mantle rock mantle lithofacies and the sulfide mantle in the mantle lithosphere The distribution of gold content is consistent, that is, the gold content in the mantle rock en masse is high, and the gold content in the mantle lithofacies sulphide phase is also high. In addition to Hainan Island, The gold content distributions of the whole rock and the enclave in the Lantau, Changle and Hannuoba mafic rocks in the south and north margin of the platform are all high, which correspond with the gold deposits in the western Hebei and Shandong Jiaodong Peninsula Relationship, reflecting that the high gold content of the mantle may provide the material for the formation of gold deposits in the corresponding area Based on the material foundation of the primitive mantle in the ancient North China platform, which was still rich after the mantle event in the late stage, it shows that mantle events (such as thinning, atrophy, undergrowth, detachment, replacement, accountability, etc.) The relevant CO2-rich gold-bearing mantle fluids activate, enrich and migrate gold until mineralization occurs on the material basis of the pre-lithospheric mantle.