岩浆中心成矿系——岩浆岩体和矿床组合的空间分带理想模式  

Ore-forming System around Magma—Model of Spatial Zonation for Magmatic Rock and Deposit Set

作　　者：岑况[1] 田兆雪[1] 

机构地区：[1]中国地质大学地球科学与资源学院,北京100083

出　　处：《现代地质》2012年第5期1051-1057,共7页Geoscience

基　　金：中国地质调查局项目(1212011120205)

摘　　要：系统总结和分析了当前大量热液金属矿床与岩浆岩体的空间和成因关系,参考首先由俄罗斯地球化学家提出的以矿床为中心的元素地球化学理想分带模式,提出了以岩浆岩为中心的矿床理想分布模式——"岩浆中心成矿系"。该模式以侵入近地表含水围岩的岩浆岩体顶部为中心,一个完整的高温矿床→中温矿床→低温矿床从内带—过渡带—中带—外带有规律分布。内带主要为Nb、Ta、Hf、Li等经常在岩浆岩体内生成的矿床,形态受岩浆岩体控制,多为等轴状;过渡带为W、Sn、Mo、Bi等高温热液矿床,形态以三维等轴状为主;中带为Cu、Pb、Zn等中温矿床,以透镜状、脉状为主;外带为Au、Hg、Sb等低温矿床,矿体呈脉状、串珠状,受构造线控制,顺从构造线分布。矿床系列围绕岩浆中心成矿有独特的形成过程:岩浆岩侵入含水围岩后,形成局部高温度场并导致热液和矿床物质循环和温度场内的时空温度差是岩浆中心成矿系形成的关键。在理想模式下产生的个体(岩体矿床组合体)同时受到形成条件的影响:岩浆体侵入的深度、围岩的岩性或含水性,岩浆的物理化学性质、侵入温度、岩浆规模都会导致岩浆中心成矿系的完整性和形态等变异。According to the spatial and original relationship between current hydrothermal metal deposits and magmatic body,and referring to the ideal mode of deposit element zone which is proposed first by Russian geochemist,this paper puts forward the ideal mode of the distribution of the magma hydrothermal deposits,which is also called ＂ore-forming system around magmatic rock center＂.This mode is centred on the top rock mass which intrudes to the near-surface surrounding rocks,and it is divided into inner-zone,transition-zone,medium-zone and outer-zone.The mode scatters by hypothermal deposits,mesothermal deposits and epithermal deposits from inner-zone to outer-zone regularly.Inner-zone is mainly distributed by the deposits which usually form in the magmatic rock such as Nb,Ta,Hf,Li.These deposits are equiaxed shapes because they are controlled by the magmatic rocks.Transition-zone is mainly distributed by hypothermal deposits such as W,Sn,Mo,Bi,which are mostly three-dimensional.Medium-zone is mainly distributed by mesothermal deposits such as Cu,Pb,Zn with lenticular shape and vein shape.Outer-zone is mainly distributed by epithermal deposits such as Au,Hg,Sb,which are mostly nervation and beaded shape along the tectonic fissure.Ore forming around the magmatic center has its own unique formation process： after magmatic rock intruding to the hydrous surrounding rock,there is a partly high temperature field which is the key leading to the hydrothermal deposits material cycle and spatial and temporal temperature difference in the temperature field.Individuals which formed under the ideal mode are controlled by the forming condition： the depth of intrusive magmatic rock,the lithology or property of water-bearing of surrounding rock;physicochemical property of magma,intrusive temperature,magma scale can all cause the integrity of magmatic center metallogenic series and shape variation.

关 键 词：岩浆中心 成矿系 矿床分带理想模式 个体生成法则 

分 类 号：P611.11[天文地球—矿床学] P595[天文地球—地质学]