摘要
喀腊大湾地区位于阿尔金山脉东北缘,当地早古生代时期构造环境复杂并且伴随剧烈的花岗质岩浆活动.通过对区域内早古生代中酸性侵入岩5个岩体(大平沟岩体、阿北银铅矿岩体、阿北岩体、4337北花岗岩体、喀腊大湾南岩体)的岩石学、岩相学、地球化学特征研究,探讨早古生代区域重大构造事件和构造环境.南部的喀腊大湾南岩体表现低钾性质,其余4个岩体样本为中高钾钙碱性中酸性岩,并且有向高钾演变的趋势,铝饱和指数在1.0~1.1之间,数据统计和分析大部分样品具有I型花岗岩特征,少部分显示了I型向S型过渡的性质,代表了洋壳-陆壳活动性大陆边缘的环境.结合喀腊大湾周边地质背景,本地区应该是阿尔金古洋壳和塔里木地块南北向碰撞作用的火山岛弧区域.
The Kaladawan area is located in the northeast of Altun Mountains,where the Early Paleozoic tectonic settingswere complicated,accompanied by intense granitic magmatism.Based on the research of petrology,geochemistry and geochronology of the Early Paleozoic acid-intermediate intrusive rocks in this area,the regional geological events and tectonic settings are discussed.Four of the five plutons in this study are characterized by high-K calc-alkaline.The other presents low-K character.Most of the samples analyzed show the characteristics of Ⅰ-type granite,with a few as transitional products from Ⅰ-type to S-type,indicating the active continental margin environment of oceanic-continental crust.Regards Combining the surrounding geological background,this region should be the volcanic island arc when the ancient Altun oceanic crust collided with Tarim massif.
出处
《地质与资源》
CAS
2014年第4期369-375,共7页
Geology and Resources
基金
"十二五"国家科技支撑计划项目新疆跨境成矿带战略性矿产资源预测与靶区评价专题"阿尔金成矿带多元信息成矿预测与找矿示范"(编号2011BAB06B08-04)
中国地质调查局地质矿产调查专项"阿尔金喀腊大湾地区铁多金属矿构造控矿研究与找矿预测"(编号1212011085043)联合资助
关键词
阿尔金山
早古生代
花岗岩
地球化学
构造环境
Altun Mountains
Early Paleozoic era
granite
geochemistry
tectonic setting