大陆冲磁效应对成矿作用的控制  

METALLOGENESIS CONTROLLED BY CONTINENTAL CLASH-MAGNETISM

作　　者：孙忠实[1] 邓军[2] 孙黎[1] 白岩[1] 范思琦[1] 王建平[2] 杨立强[2] 王庆飞[2] 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]中国地质大学地球科学与资源学院,北京100083

出　　处：《地质科学》2007年第4期812-824,共13页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金(批准号:40272051;40572063);国家自然科学重点基金(批准号:40234051)资助

摘　　要：物体受到冲击或两种地质体界面发生快速磨擦引发地磁异常或岩石剩磁的变化称之为冲磁。本文以陨石成矿和走滑构造控矿为例,通过瞬间附加磁力的产生和能量守恒的原理探求大陆冲磁效应对成矿作用的控制。1)根据陨石的平衡和运动规律,运用冲磁强度值可初步估算矿体的总量;通过冲磁的矢量,可确定陨石成因的矿体侧伏产状。2)大陆冲磁和矿物成份两者相互印证可共同确定成矿时代。3)大陆冲磁的连续介质力学和总量守恒(陨石体的质量、动量和能量与矿体的质量、动量和能量守恒)对成矿元素富集的控制,巨大的冲磁强度值与高温岩浆矿床Fe、Co和N i等铁磁性元素富集相对应。4)大陆冲磁引发多元流体对组合元素富集的控制,冲磁在陨石体内形成高温成矿元素组合,在围岩内则形成低温成矿元素组合。5)大陆冲磁时的剪切效应对成矿元素富集的控制。与冲磁垂直的方向有利于成矿元素的富集;冲磁—应变速率—元素自身磁化率值的共同效应控制多种元素呈侧向分带展布。冲磁效应对成矿作用的控制将拓宽和加大大陆动力学与成矿作用间的研究内容和深度。The clash-magnetism means that object clashings or speed attritions give rise to geomagnetism abnormity. The paper, taking the Hongqiling Cu-Ni deposit as an example of meteorolite impact and the gold deposits along the Tan-Lu fault zone as an instance of shearing controlling metallogenesis, dealt with that metallogenesis was controlled by continental clash-magnetism, since the instant additions of magnetism and conversation of energy during the continental clash-magnetism. The main views were as follows. 1 ） Ore grosses were estimated by the meteorolite sport and numerical value of the clash-magnetism, and occurrence of ore body was ascertained on the basis of the clash-magnetism vector. 2） Test and verify of the clash-magnetism and elements ascertains could decide the metallogenetic epoch. 3） Continual medium mechanics and grosses conservation of the clash-magnetism controlled the enrichment of the metallogenetic elements. The huge clash-magnetism vector related to Fe-Co-Ni element＇s enrichment of high temperature magma deposit. 4） The continental clash-magnetism resulted in many kind of liquids, and controlled the enrichment of combining elements. The clash-magnetism caused the element combination of high temperature in the meteorolite body, and the element combination of low temperature in the wall rocks. 5） The shear effect of the continental clash-magnetism controlled the element＇s enriching. The direction of perpendicular to the clash-magnetism might be favorable to the ore-forming element＇s enrichment. In addition, the total effect of the clashmagnetism, strain speed and magnetization rate controlled the lateral distribution of many oreforming elements. The effect study of clash-magnetism controlling metallogenesis might widen and deepen further the relational fields of continental dynamics and metallogenesis.

关 键 词：冲磁效应 成矿作用 元素富集 剪切带控矿 

分 类 号：P611[天文地球—矿床学]