低温热液成矿与米仓山大火地金矿特征分析

Low temperature hydrothermal mineralization and analysis of the characteristics of gold deposits in the micangshan fire area

在扬子准地台北缘,米仓山台穹内,上两复背斜的前震旦纪结晶基底中,核部地层为麻窝子组。在该区域内针对四川省南江县大火地金矿矿脉产于北西南东向节理和裂隙中,严格受节理和裂隙控制,矿脉产状多受构造产状限定,围岩蚀变也沿矿脉所处的构造呈线状展布,说明矿脉是矿液沿早期构造空间充填而成;矿床中围岩蚀变主要有绿泥石化、绢云母化等,属一套中低温热液蚀变组合,据此推断该矿床成因为构造控制的中低温岩浆期后热液金矿床。

in the Precambrian crystalline basement of the upper two anticlinorium in the micangshan dome on the Taibei margin of the Yangtze quasi-region,the nuclear formation is the mawazi formation.In this area,the vein of huoshandi gold mine in Nanjiang county,Sichuan province is located in the joints and fissures in the southeast of north and strictly controlled by the joints and fissures.the occurrence of the vein is mostly limited by the structural occurrence.the alteration of the surrounding rock is also distributed linearly along the structure where the vein is located,which shows that the vein is filled by the ore fluid along the early structural space.The wall rock alteration in the deposit mainly includes chloritization and sericitization,which belongs to a set of medium-low temperature hydrothermal alteration assemblage.based on this,it is inferred that the deposit is formed by the post-magmatic hydrothermal gold deposit controlled by the structure.