核幔成矿物质(流体)的反重力迁移——地幔热柱多级演化成矿作用  

THE ANTI-GRAVITY MIGRATION OF METALLOGENIC FLUID FROM CORE AND MANTLE

作　　者：牛树银[1] 侯增谦[2] 孙爱群[1] 

机构地区：[1]石家庄经济学院资源环境与工程系,河北石家庄050031 [2]中国地质科学院矿床地质研究所,北京100037

出　　处：《地学前缘》2001年第3期95-101,共7页Earth Science Frontiers

基　　金：原地矿部"跨世纪科技人才培养计划项目"( 96 0 8) ;教育部高等学校骨干教师资助计划项目 (J 0 0 2 5 )

摘　　要：地壳中矿床分布极不均匀 ,这与地球的形成与演化密切相关。在地球演化的早期 ,由于在引力收缩和热力膨胀的统一作用支配下 ,放射性、卤族、稀有、稀土元素及碱金属向上迁移 ,而贵金属、有色、铁族、铂族等密度较大的元素则有逐渐向地核聚集的趋势 ,以至于铁、镍、金等元素主要聚集在地核之中。但是 ,在地球形成圈层结构的同时 ,由于地球内外温度差、压力差、粘度差等的存在 ,导致地球发生以地幔热柱多级演化为主要形式的垂向物质运动 ,两者互为依存 ,并构成幔壳运动的原动力。地幔热柱多级演化沟通了深部矿质的迁移通道 ,聚集在地核及核幔界面上的气态金等重元素得以作为地幔热柱的热物质流 ,呈反重力迁移至岩石圈 ,并进而以气 液态向近地表迁移 ,在有利的构造扩容带中聚集成矿。这可能是金银铜铅锌等多种元素的重要成矿作用方式。The distribution of the mineral deposits is nonhomogeneous throughout the crust. This is contributed to the formation and evolution of the Earth. At the beginning, the Earth evolution was uniformly dominated by gravitational contraction and thermal expansion,as a result,radioactive elements, halogen elements, rare elements, REE and alkali metal migrated upward. The high special gravity elements such as noble metal, nonferrous, iron group and platinum group tended to be concentrated to the core,and the noble elements such as iron, nickel, gold mainly concentrated toward the core. However, during the layering evolution of the Earth, the differences in temperature, pressure and viscidity within the Earth led the substance of the Earth up to vertically moving in form of multiple evolution of mantle plume. This is the motivity of mantle-crust movement. Multiple mantle plume evolution opened out migration channel for deep substance. The heavy metal elements such as gaseous gold that concentrated in core or at interface between the core and mantle took the form of thermal fluid in mantle plume. They moved up to lithosphere in anti-gravity migration and further came to the crust near surface taking the form of thermal fluid. They could deposit in favorite enlarged structures to form deposits. This might be important metallogenic process for the mineralization of Au, Ag, Cu, Pb, Zn etc.

关 键 词：地幔热柱 幔枝构造 反重力迁移 成矿作用 构造扩容带 成矿元素 

分 类 号：P611[天文地球—矿床学] P542.5[天文地球—地质学]