地形环境对海底热液硫化物矿体内部流体循环的影响  

Influence of Topography on the Hydrothermal Circulation within the Hydrothermal Sulfide Deposit

作　　者：李怀明[1] 翟世奎[2] 于增慧[2] 初凤友[1] 陶春辉[1] 

机构地区：[1]国家海洋局海底科学重点实验室 [2]中国海洋大学海洋地球科学学院,山东青岛266100

出　　处：《地球科学（中国地质大学学报）》2008年第4期538-546,共9页Earth Science-Journal of China University of Geosciences

基　　金：国家重大基础研究发展规划项目(No.G2000078503);中国大洋协会项目(No.DY115-02-1-01)

摘　　要：在三层结构热液硫化物矿体模型的基础上,分别构建了具有不同地形环境的海底热液硫化物矿体模型,利用数值模拟方法,模拟了具有倾斜海底面和起伏地形特征的硫化物矿体模型内部温度场和流场分布,并据此探讨了地形环境在大型海底热液硫化物矿体形成过程中的控制作用.模拟结果表明:(1)倾斜的洋壳层顶面对于矿体内温度场和流场分布的影响程度有限;(2)矿体地形起伏是控制矿体内流体运移和热场分布的重要因素;(3)在热液流体喷出区附近硫化物的堆积速度较快,易于形成矿体的高地形区;但随着地形的不断升高,矿体内部的温度场和流场的分布模式会逐渐发生改变,导致该区域热液喷口逐渐消亡或者改道.Based on the three-layer model of seafloor hydrothermal sulfide deposit, the deposit models with diverse topography have been built. With numerical approach, the distribution of inner thermal and flow fields of the large hydrothermal sulfide deposit model featuring sloping crust and relief top is simulated to discuss the effect of the different relief on the forrnation processes of the hydrothermal sulfide deposit. The results indicate： （1） the sloping seafloor has a limited influence on the distribution of thermal and flow fields within the hydrothermal sulfide deposit. （2） The relief top is one of the dominating factors that control distribution of the thermal and flow fields within the hydrothermal sulfide deposit. （3） Hydrotherrnal sulfides precipitate and accumulate rapidly near the region of focused venting, thus easily forming high relief. As the continuous rising of this high relief, the distribution mode of the thermal and flow fields gradually changes, which causes the hydrothermal venting to gradually cease or redirect.

关 键 词：海底热液活动 硫化物矿体 流体循环 地形 

分 类 号：P628[天文地球—地质矿产勘探]