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对湖南、贵州剖面的上下岩层的硅质岩、磷块岩、重晶石岩、金属富集层的沉积海水的温度、深度、介质条件、生态条件进行研究,硅质岩沉积期古海水温度平均为84.81℃或87.27℃,磷块岩沉积期古海水温度平均为42.17℃,磷块岩的形成温度与硅质岩比较相似,<100℃,分别约为37～47℃、79～98℃。研究区水深变化在100～300 m之间。硅质岩、富硫化物黑色页岩(金属富集层)、重晶石生成于微碱性的介质环境。而磷块岩生成于微酸性-微碱性的介质环境。成岩成矿模型研究充分揭示亲基性元素Ni、Mo、V、Cr、PGE的存在与基性岩、超基性岩的成因联系。研究区域在早寒武世期间属于东特提斯海域,中国南部板块和澳大利亚板块于早寒武纪分离期间所形成的深大断裂带,正可能是海水进行深部循环吸取镁铁质下地壳PGE形成富金属热卤水而在海底沉积的通道。
The temperature, depth, media conditions and ecological conditions of the sedimentary seawater in the upper and lower strata of Hunan and Guizhou stratigraphy are studied. The seawater temperature Averaged 84.81 ℃ or 87.27 ℃. The average temperature of ancient seawater during phosphorite deposition was 42.17 ℃. The formation temperature of phosphate rock was similar to that of siliceous rocks, <100 ℃, respectively, at 37-47 ℃ and 79-98 ℃ . The water depth of the study area varies between 100 and 300 m. Silicalite, sulfide-rich black shale (metal enrichment layer), barite generated in a slightly alkaline media environment. Phosphorite is formed in a slightly acidic - slightly alkaline media environment. Diagenetic metallogenic model fully reveals the genetic relationship between the presence of Ni, Mo, V, Cr, PGE and the basic and ultrabasic rocks. The study area belonged to the Eastern Tethys area during the Early Cambrian. The deep fault zone formed during the period of the Precambrian separatism between the southern China plate and the Australian plate may be the result of deep seawater recirculation of mafic lower crust PGE A metal-rich hot brine forms on the seafloor.