地质与资源2025，Vol.34Issue(2)：137-147,11.DOI:10.13686/j.cnki.dzyzy.2025.02.001
辽东刘家河地区古元古代花岗闪长岩年代学、地球化学及地质意义
Geochronology and geochemistry of Paleoproterozoic granodiorite in Liujiahe area,eastern Liaoning Province:Geological implication
摘要
Abstract
A large number of granitic rock mass exposed in eastern Liaoning Province serves as a critical medium for investigating the tectonic evolution history of Paleoproterozoic Jiao-Liao-Ji orogenic belt.Through the study of petrology,chronology,and geochemistry of the Paleoproterozoic granodiorites in Liujiahe area of eastern Liaoning Province,this paper determines the genesis and further explore the tectonic attributes of Paleoproterozoic Jiao-Liao-Ji orogenic belt.The study shows that the zircon U-Pb dating of granodiorite yields a weighted mean age of 2 180.7±9.0 Ma,indicating its Paleoproterozoic formation.The SiO2 content is 66.39％-71.65％(averagely 69.11％),Al2O3 11.35％-15.58％(averagely 12.67％),K2O+Na2O 7.22％-9.05％(averagely 7.89％),K2O/Na2O 0.53-0.59(averagely 0.55),with high content of CaO(0.65％-4.12％,averagely 2.44％)and MgO(0.16％-0.86％,averagely 0.51％).The sample is of calc-alkaline to high-K(calc-alkaline)series,with A/CNK of 0.63-1.10 and A/NK of 1.06-1.20,belonging to metaluminous-peraluminous rocks,characterized by low REE content,and relatively depletion of HFSEs(Nb,Ta,Ti,Ba),showing the characteristics of Ⅰ-type granites.The geochemical characteristics indicate that the granodiorite is originated from the partial melting of felsic crust under low-pressure conditions,with distinct island arc magmatic features.In the tectonic discrimination diagram,all samples plot within the volcanic arc granite field,indicating the subduction-induced arc magmatism in Liao-Ji orogeny during early Paleoproterozoic(2.2-2.1 Ga).关键词
花岗闪长岩/古元古代/地球化学/地质年代学/弧陆碰撞/辽宁省Key words
granodiorite/Paleoproterozoic/geochemistry/geochronology/arc-continent collision/Liaoning Province分类
天文与地球科学引用本文复制引用
吴文彬,张德军,张楠,李崴崴,王玉平,王晓亮,李海洋..辽东刘家河地区古元古代花岗闪长岩年代学、地球化学及地质意义[J].地质与资源,2025,34(2):137-147,11.基金项目
中国地质调查局项目"内蒙古1∶5万朝阳沟幅(L50E023017)、老房身幅(L50E024017)区域地质调查"(DD20242884)、"东北地区地层古生物地质调查"(DD20230220) （L50E023017）
辽宁省科学技术计划项目"西拉木伦河北岸半拉山杂岩成因对华北板块北缘晚古生代早期构造演化的启示"(2024-BS-302) （2024-BS-302）
中国地质调查局东北地质科技创新中心区创基金项目"内蒙古巴林右旗南部晚石炭—早二叠世岩浆作用及其地质意义"(QCJJ2023-25). （QCJJ2023-25）
