摘要
西天山阿吾拉勒成矿带广泛发育的大哈拉军山组火山岩为以一套流纹岩、粗面岩、粗面安山岩、中酸性凝灰岩和少量玄武岩为主体的火山岩-沉积岩建造。本研究运用LA-ICP-MS锆石U-Pb法,厘定了松湖铁矿、式可布台铁矿、备战铁矿火山岩的成岩时代,并系统整理阿吾拉勒铁矿成矿带上已经获得的高精度年代学数据,确定阿吾拉勒成矿带大哈拉军山组火山岩的时间分布规律为自西向东渐变的特征,在年代上表现为自西向东呈由老变新的趋势,早石炭世火山岩从西向东表现为尖灭的特征,在岩性上具有安山岩-玄武安山岩-粗面质火山熔岩-火山碎屑岩变化的特点。在此基础上,结合遥感影像特征,确定大哈拉军山组火山岩的空间分布特征,进一步提取破火山口的特征,判断其与典型矿床之间的位置关系,探讨典型矿床与火山机构在成因上的联系,结合大地构造演化特征,探讨其地质意义。
There exist widely- developed volcanic rocks of Dahalajunshan Formation along the Awulale metallogenic belt in West Tianshan Mountains. They are volcano- sedimentary rocks composed mainly of a set of rhyolite, trachyte, trachyandesite and intermediate- acidic tuff as well as a small amount of basalts. In this paper, the authors used LA- ICPMS zircon U- Pb dating method to determine the rock- forming age of volcanic rocks from Songhu, Shikebutai and Beizhan iron ore deposits. In addition,the authors sorted out the high- precision geochronological data previously obtained from the Awulale metallogenic belt. There exists the gradual change regularity from west to east： Chronologically, the age tends to change from old to young eastward, the Early Carboniferous volcanic rocks tend to pinch eastward, and the lithologic character varies in order of andesite lithology-basaltic andesite- rough endoplasmic lava- pyroclastic rocks. On the basis of data obtained and remote sensing image features, the authors determined the temporal and spatial distribution of the volcanic rocks in Dahalajunshan Formation, extracted the characteristics of the caldera and judged the spatial relationship between typical ore deposits and the caldera, thus investigating the genetic relationship between typical deposits and volcanic apparatuses. In combination with tectonic evolution characteristics, the geological significance is also discussed.
出处
《中国地质》
CAS
CSCD
北大核心
2015年第3期570-586,共17页
Geology in China
基金
中国地质调查局国土资源大调查项目"西天山阿吾拉勒晚古生代火山作用与铁铜矿选区评价研究"(12120113044000)
"西天山阿吾拉勒成矿带铁矿成矿条件
成矿规律与勘查示范研究"(1212010880202)
国家自然科学基金项目"新疆东准噶尔卡拉麦里金矿带成矿流体特征及其侵入体的关系研究"(41462004)联合资助
