吉林省夹皮沟—金城洞花岗绿岩带中金矿床的形成时代  

THE FORMATION AGE OF GOLD DEPOSITS IN THE JIADIGOU—JICHENGDONG GRANITEGREENSTONE BELT IN JILIN PROVINCE

作　　者：刘劲鸿 

机构地区：[1]吉林省地质科学研究所

出　　处：《吉林地质》1989年第4期58-70,共13页Jilin Geology

摘　　要：众所周知,太古宙绿岩带是世界上主要含金岩系,有“金矿带”之称。夹皮沟—金城洞花岗绿岩带同样是驰名中外的金矿带,著名的夹皮沟金矿就产于其中。该带呈向北凸弧形,西起石棚沟,东止金城洞,长约250km,宽3.O—30km。它由下部镁铁质基性火山岩、中部中酸性火山岩及上部火山—沉积的含铁岩和少量沉积岩组成。在漫长的地质史中经历了多期变质变形作用,变质程度为中高—中低角闪岩相。该带中矿床(点)均产于下部或中下部。金矿带被花岗岩和两江断裂截成三段,即西段石棚沟金矿田(Ⅰ),中段夹皮沟金矿田(Ⅱ)和东段金城洞金矿田(Ⅲ)(图1)。大中型矿床均产于Ⅱ矿田中,因此Ⅱ矿田为研究的重点。The gold deposits in the Jiapigou-Jinchengdong greenstone belt have a stratabound characteristics in space,especially in the Jiapigou ore field.The greenstone is a source bed,belonging to basis for metallogeny,and tectonic deformtion is a drive force for metallogeny.In 2500-2400Ma,the first pro- gressive metamorphism—viscous deformation and its assdciation with in- trusion of remelted granite is thermodynamic process for metallogeny of gold. In 2400-1600,the second retrogressive metamorphism-ductile deformation and its association with intrusion of potassium granite is a key factoror for promoting transformation from mineralization into formation of ore deposits.The main lodes are cut by phanerozoic veins,characterized by the banded and brecciated struc- ture with brittle deformation.The petrofabric characteristics,ore-forming fluid(H_2O-CO_2),pressure(1.2-1.8)and high percentage of gold etc. all show that the main lodes are resulted from the transformation from duc- tile to brittle deformation in the ductile shear zone(D.S.Z.)of greenstone belt in the late stage.The emplacement mechanism coincides with the expe- rimental results of Riede,so,the main lodes are part of D.S.Z..After the emnplacement of the main lode,it underwent the evolution of D.S.Z.,and gold was concentrated with activities.The geochronologicl research indica- tes that times of emplacemnet is early proterozoic(1900-1600 Ma).The phanerozoic magmatic activities are not intenssive in the ore fieid,and are far away from the orebody,and no comercial oreoodies are found in the vicinity of this mine.

关 键 词：金矿床 花岗绿岩带 形成时代 成矿流体 矿床地质 同位素地球化学 

分 类 号：P618.51[天文地球—矿床学] P597[天文地球—地质学]