全球现代海底块状硫化物矿床资源量估计

A GLOBAL ESTIMATE OF RESOURCE POTENTIAL FOR MODERN SEAFLOOR MASSIVE SULFIDE DEPOSITS

随着世界发展对各种资源需求量的增大,海底资源究竟有多少也已成为全球各界探索的热点问题。现代海底块状硫化物(SMS)作为当今重要的潜在海底金属矿产资源,已在全球各个海域被广泛勘探和调查研究。在国际海底管理局建立的全球海底热液活动数据库基础上,利用美国地质调查所海底矿产评价"三部法",即:(1)将洋中脊、海底火山弧、弧后扩张中心圈定为全球SMS矿床远景区;(2)选定验证SMS矿床适用的矿床吨位、品位模型;(3)根据质通量、热通量、热液柱以及控制区数据估计全球热液喷口区数量与SMS矿床数量,对现代海底SMS矿床的资源量进行初步估计。结果显示:全球现代SMS矿床约为1 000个,所含资源量约为6×108 t,其中铜、锌、铅金属量为3×107 t,与陆地新生代以来的火山块状硫化物(VMS)矿床1.9×107 t相近。

Mining seMloor massive sulfide （SMS） deposits has been increasingly concerned by the geological society. However, the global resource potential remains unclear to the present. Based on the data of Glob- al Database of Seafloor Hydrothermal Systems, we make a global estimate of resource potential for the SMS according to the 3-part mineral assessment practice provided by the U. S. Geological Survey. Firstly, the distribution of SMS deposits is examined, and mid-ocean ridges, volcanic arcs, and back-arc spreading centers are selected as the permissive areas for discovery of new deposits. Secondly, the available SMS de- posit tonnage and grade model are chosen to calculate the average resource potential. Thirdly, the number of high-temperature hydrothermal vent and SMS deposits was estimated according to the data of mass flux, heat flux, hydrothermal plume and control areas. The results reveal that the number of SMS deposits is a- bout 1 000, and the total resource potential is estimated to be 6 × 108 tons, containing about 3 × 107 tons of copper, zinc and lead.