摘要
东昆仑造山带西段矿产资源丰富,岩石种类繁多,是我国西部重要的矿产生产基地。为加深对此区域构造演化和成矿规律的认识,选取了夏日哈木—锡铁山成矿带岩石作为研究对象,通过对岩石样品光薄片观察、主微量元素分析进行了岩矿和地球化学方面的研究,探讨了其岩石成因,及其构造环境。研究初步认为,该区的超基性岩中含有较多的金属矿物,Fe2O3和FeO的含量高,高场强元素Th、U、Y、Hf富集,轻重稀土分馏明显,Ce存在轻微负异常,表明有地壳物质加入的亏损尖晶石相地幔橄榄岩向石榴石相地幔橄榄岩过渡的部分熔融,判断其构造环境为大陆裂谷环境;基性岩中含有较多的钾长石和斜长石,CaO和Na2O+K2O的含量高,属钙碱性岩石,高场强元素Nb、Zr、U、Ta亏损,Rb、Sr富集,轻重稀土分馏明显,Eu存在正异常,Ce存在轻微负异常,岩石的物质来源既与地幔有关也与下地壳有关,形成的构造环境为岛弧环境,产出部位在靠近大陆的一侧。
The western part of the East Kunlun orogenic belt is rich in mineral resources and various kinds of rocks.It is an important mineral production base in western China.In order to deepen the understanding of the tectonic evolution and metallogenic regularity in this area,the rocks in Xiarihamu-Xitieshan metallogenic belt are selected as the research object.Through the observation of the polished thin section and the analysis of the major elements or trace elements of the rock samples,the rock ore and geochemistry were studied,the petrogenesis of the rock and its tectonic environment are discussed.The research preliminary shows that the ultrabasic rock contains more metal minerals,high content of Fe2O3 and FeO,high field strength elements Th,U,Y,Hf are enriched,light and heavy rare earth obvious fractionation,Ce has a slight negative anomaly.It indicates that the partial fusion of the transition from deficit spinel-phase mantle peridotite to garnet-phase mantle peridotite,with crustal material added.It is judged that the tectonic environment is continental rift environment.The basic rock contains more K-feldspar and plagioclase,high content of CaO and Na2O+K2O,it belongs to calc-alkaline rock.The high field strength elements Nb,Zr,U and Ta are deficit,Rb and Sr are enriched,light and heavy rare earth obvious fractionation,Eu has a positive anomaly,Ce has a slightnegative anomaly.The material source of the rocks is related to both the mantle and the lower crust.The tectonic environment formed is an island arc environment,and the production site is on the side close to the continent.
作者
张世珍
王建国
宋振国
李国荣
任海东
ZHANG Shizhen;WANG Jianguo;SONG Zhenguo;LI Guorong;REN Haidong(Department of Geological Engineering,Qinghai University,Xining 810016,China;State Key Laboratory of Mineral Processing,Beijing 102628,China)
出处
《有色金属工程》
CAS
北大核心
2021年第1期116-125,共10页
Nonferrous Metals Engineering
基金
青海省应用基础研究计划项目(2019-ZJ-7022)
矿物加工科学与技术国家重点实验室开放基金(BGRIMM-KJSKL-2020-04)。
