海洋底层水成矿金属组分存在形式和沉淀矿物的定量研究  

Quantitative Study on Precipitable Mineral and the Existing Form of Ore-forming Metal Species of the Bottom Water in Ocean

作　　者：张宏达[1] 汪珊[2] 杨振京[2] 李政红[2] 

机构地区：[1]中国地质大学,北京100083 [2]中国地质科学院水文地质环境地质研究所,河北正定050803

出　　处：《地理与地理信息科学》2003年第2期56-59,共4页Geography and Geo-Information Science

基　　金：国家自然科学基金资助项目(49902021)

摘　　要：该文以测试资料为依据,以溶液化学平衡反应模型理论计算为手段,对海盆和洋盆底层水的成矿金属组分存在形式和沉淀矿物进行定量计算,发现海洋底层水系统为非平衡的地球化学动力系统,系统中发生着活跃的物质和能量交换与转移,海洋底部现代正在发生沉淀作用。海洋底层水是一种典型的稀金属成矿溶液,除Fe在洋盆存在高价态外,Fe的其它组分形式及Mn、Cu、Ni、Co4种金属组分均以低价态的组分形式存在,它们不可能通过化学沉淀作用生成以高价态锰矿物为主的结核。Mn、Fe主要以胶体和微粒形态存在,其浓度比溶解态的浓度要高出数百倍甚至千倍。这些胶状的金属微粒流直接参与结核的生成,胶体化学作用是结核生成的主要成矿作用。Based on the data of samples and experiments, a quantitative estimation for ore-forming metal species in ocean bottom water in the South China Sea and the eastern Pacific and their precipitation to minerals was carried out by means of the geochemical equilibrium model. It is deduced that the bottom water system is a no-equilibrium geochemical dynamic system, in which is taking place the active exchanges and transformation of energy and mass between water and depositions, and the modern mineral deposition has been engendering in this system. Except for high valence Fe, other Fe and Mn, Cu, Ni and Co occur in low valence although the bottom water is a typical metal ore-forming diluted solution. Thus, the high valence Mn-dominated nodule cannot be formed by chemical precipitation. On the contrary, the Mn and Fe existed as the colloid and particle form in the water, which's concentrations are hundreds to thousands times higher than solution, directly participate in nodules forming. The colloidal chemical action is the dominated nodule-forming process.

关 键 词：底层水 成矿金属组分 存在形式 溶解-沉淀作用 海洋 

分 类 号：P736[天文地球—海洋地质]