南秦岭龙头沟金矿床石英Rb-Sr同位素测年及其地质意义OACSTPCD
Rb-Sr age dating of quartz from Longtougou Au deposit in South Qinling area and the geological significance
龙头沟金矿位于柞(水)—山(阳)矿集区中部,矿床受构造控制,赋矿地质体主要为重晶石黄铁矿化石英脉,近年来相继在其外围发现五条沟、宽坪沟等金矿床,形成了一条重要的金矿带,成矿时代不清始终制约着对该矿床的进一步工作.为此,本文以主成矿阶段石英流体包裹体Rb-Sr同位素测年为主要手段,开展成矿年代学研究.研究表明,该矿床是印支晚期构造热液活动的结果,其成矿作用可能开始于～266 Ma,以五条沟矿段249 Ma±42 Ma为代表达到高峰.南秦岭山凤断裂沿线,自海西期以来,构造-岩浆-热液活动呈现出三期活动显著特点,成岩成矿高峰期为280 Ma-300 Ma、200 Ma-220 Ma和140 Ma-160 Ma,丰富的岩浆热液活动不但给成矿作用带来大量的深部成矿物质,还直接控制着矿化强度、期次以及叠加成矿作用,龙头沟金矿与其他较大规模金矿一样,都是印支-燕山早期构造活动的结果,是南秦岭印支期金成矿作用的体现.
Iongtougou Au deposit is located in the central Zhashui-Shanyang Au deposit-clustered area.It is tectonically controlled and hosted by barite-quartz vein and forms a major Au ore belt together with Wutiaogou and Kuanpinggou Au deposits discovered in the surrounding in resent years.Making clear of ore-forming ages will expand exploration targets.Rb-Sr age dating is conducted on fluid inclusion of quartz.The result shows that the Au deposit are resulted from late Indo-China hydrothermal activity.The ore-forming process started from about 266 Ma.The age dating of Wutiaogou Au deposit is 249 Ma±42 Ma.Along Shanfeng fault took place three major tectonic-magnetic hydrothermal activities since Hercynian epoch with rock-forming and ore-forming stages of 280 Ma-300 Ma,200 Ma-220 Ma and 140 Ma-160 Ma.The abundant hydrothermal fluid and intense hydrothermal activity provided not only huge volume of ore materials from depth but also controlled directly epoches and intensity and over printing of mineralization.Similar to other large Au deposits Longtougou Au deposit is the result of tectonic move-ment from Indo-China to early Yanshanian period representing Au ore-forming process in Indo-China period.
刘新伟;薛玉山;寸小妮
西安西北有色地质研究院有限公司,西安 710054||中国地质学会新能源矿产勘查与综合利用创新基地,西安 710054||陕西省矿产资源综合利用工程技术研究中心,西安 710054西安西北有色地质研究院有限公司,西安 710054||中国地质学会新能源矿产勘查与综合利用创新基地,西安 710054||陕西省矿产资源综合利用工程技术研究中心,西安 710054西安西北有色地质研究院有限公司,西安 710054||中国地质学会新能源矿产勘查与综合利用创新基地,西安 710054||陕西省矿产资源综合利用工程技术研究中心,西安 710054
地质学
龙头沟金矿床石英流体包裹体Rb-Sr同位素印支期南秦岭成矿时代
Longtougou Au depositRb-Sr isotopes of quartz fluid inclusionIndo-China epochore-forming periods in South Qinling area
《地质找矿论丛》 2024 (4)
469-477,9
西安西北有色地质研究院有限公司科研项目(编号:2021J022023J02)资助. 本文为西安西北有色地质研究院有限公司科研项目(2017J02)部分研究成果,项目在实施过程中受到张云峰总经理、胡西顺总工程师等大力支持,山阳纵横矿业公司雷永康总经理、权斌副总经理等在样品采集过程中提供了帮助,在此一并表示感谢.
评论