辽东青城子矿集区金、银成矿时代及地质意义  

Metallogenic Epochs of Au and Ag Deposits in Qingchengzi Ore-clustered Area, Eastern Liaoning Province

作　　者：薛春纪[1] 陈毓川[2] 路远发[3] 李华芹[3] 

机构地区：[1]长安大学成矿作用及其动力学国土资源部开放研究实验室 [2]中国地质科学院,北京100037 [3]宜昌地质矿产研究所同位素地球化学开放研究实验室,湖北宜昌433003

出　　处：《矿床地质》2003年第2期177-184,共8页Mineral Deposits

基　　金：国家重点基础研究发展规划项目 (G19990 43 2 0 1)

摘　　要：为确定辽宁青城子矿集区金、银的成矿时代 ,分别以含金硅化岩和含银网脉状石英晶体内流体包裹体为对象 ,应用Rb_Sr法测得金、银成矿的等时线年龄为 (2 33± 31)Ma～ (2 34± 14 )Ma ;作为对Rb_Sr法测年结果的验证 ,又以与贵金属矿石矿物共生的热液石英为对象 ,用40 Ar/3 9Ar快中子活化法测得坪年龄tp=(2 38.78± 0 .74 )Ma～ (2 38.80± 0 .6 0 )Ma,等时线年龄ti=(2 39.4 6± 1.13)Ma～ (2 4 0 .35± 0 .88)Ma。Rb_Sr和40 Ar/3 9Ar两种方法的测年结果基本一致 ,与本区印支期岩浆活动时代〔2 17.6Ma～ (2 30 .7± 5 )Ma〕吻合。Located in eastern Liaoning Province, Qingchengzi area has an age_old mining history. Within an area of about 11×9 km, there occur a lot of Pb_Zn deposits, some of which have been mined for more than one hundred years. Recently a large Au deposit (Xiaodongjiabuzi) and a large Ag deposit (Gaojiabuzi) have been discovered. All this has made the area an important target for further exploration. Samples used in this study were taken from fluid inclusions in silicified rocks (the Xiaodongjiabuzi Au deposit), and in vein quartz (the Gaojiabuzi Ag deposit). The study yielded a Rb_Sr isochron age of (233±31) Ma～(234±14) Ma. To confirm the result, the authors used hydrothermal quartz associated with ore sulfides for quick neutron activation dating. This yielded 40 Ar/ 39 Ar plateau age of (238.78±0.74) Ma～(238.80±0.60) Ma,and isochron age of (239.48±1.13) Ma～(240.35±0.88) Ma. These results coincide well with the magmatism of Later Indochina age 〔217.6 Ma～(230.7±5) Ma〕.Indochina orogeny is the major metallogenic epoch in this area, and the tectonic events and the magmatism during this period must have been the major factors responsible for the ore_forming process. In eastern Liaoning, the age of gold mineralizations shows a trend of getting younger from west to east, and from north to south.

关 键 词：辽宁 成矿时代 金矿床 银矿床 流体包裹体 Rb-Sr法 等时线年龄 氩同位素 

分 类 号：P618.51[天文地球—矿床学] P618.52[天文地球—地质学]