地质通报2017，Vol.36Issue(5)：750-760,11.
湖南桃江地区印支期辉绿岩成因——地球化学、年代学和Sr-Nd-Pb同位素约束
Petrogenesis of diabase from Jiangshiqiao in Taojiang City, Hu'nan Province: Constrains from geochemistry, geochronology and Sr-Nd-Pb isotopes
摘要
Abstract
Zircon LA-ICP-MS U-Pb dating for diabase from Jiangshiqiao in Taojiang City of Hu'nan Province yielded an emplace?ment age of 229±2.3Ma (n=8,MSWD=1.8,2σ). The diabase is characterized by low values of potassium (K2O/Na2O=0.14~0.16), and alkali (K2O+Na2O=2.89%~2.96%) , enrichment of large ion lithophile elements and LREE and depletion of high field strength el?ements, low (87Sr/86Sr)i ratios (0.70606~0.70644),low positiveεNd(t) values (1.55~1.87) and enrichment of radioactive Pb, suggesting a mixed source of the depleted mantle (DM) and the lower crustal. In combination with previous studies, the authors hold that the di?abase was formed through partial melt of the mantle and lower crustal components by the upwelling asthenosphere during the Indo?sinian post-orogenic lithosphere extension in Hu'nan Province.关键词
辉绿岩/地球化学/年代学/Sr-Nd-Pb同位素/岩石成因/桃江地区Key words
diabase/geochemistry/geochronology/Sr-Nd-Pb isotopes/petrogenesis/Taojiang分类
天文与地球科学引用本文复制引用
金鑫镖,王磊,向华,刘重芃,段桂玲,李子云..湖南桃江地区印支期辉绿岩成因——地球化学、年代学和Sr-Nd-Pb同位素约束[J].地质通报,2017,36(5):750-760,11.基金项目
中国地质调查局项目《雪峰古陆及邻区金刚石找矿选区评价》(编号:12120113063000)和国家自然科学基金项目《粤北大宝山多金属矿床成因研究》(批准号:41302068) （编号:12120113063000）
