全文快速搜索:          
引用本文:张予杰 刘伟 朱同兴 安显银 廖忠礼. 西藏申扎县买巴地区早白垩世侵入岩锆石U-Pb 年龄及地球化学[J]. 中国地质, 2014, 41(1): 50-60.
ZHANG Yu-jie, LIUWei, ZHU Tong-xing, AN Xian-yin, LIAO Zhong-li. Zircon U-Pb age and geochemistry of Early Cretaceous intrusive rocks in Maiba area of Xainza County, Tibet[J]. Geology in China, 2014, 41(1): 50-60(in Chinese with English abstract).
【打印本页】   【HTML】   【下载PDF全文】   查看/发表评论  下载PDF阅读器  关闭
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览 1319次   下载 2537 本文二维码信息
码上扫一扫!
分享到: 微信 更多
西藏申扎县买巴地区早白垩世侵入岩锆石U-Pb 年龄及地球化学
张予杰 刘伟 朱同兴 安显银 廖忠礼1,2
1.中国地质调查局成都地质调查中心,四川成都610081;2.中国科学技术大学地球和空间科学学院,安徽合肥230026
摘要:
对中冈底斯带北部申扎县买巴地区广泛分布于石炭—二叠纪地层中的中?酸性侵入岩进行了研究,获得其中的花岗岩和石英二长岩LA-ICP-MS锆石U-Pb 年龄值分别为(110.8±0.9)Ma和(111.0±1.1)Ma,二者在误差范围内一致,表明其应该为同一期岩浆活动的产物?其总的地球化学特征是SiO2含量较高,而且均为铝质过饱和(A/CNK=1.05~1.38),并且富集Al?Th?LREE等元素,其中Th 丰度为14.8×10-6~28.4×10-6,暗示它们很可能与中上地壳物质有关;与上部陆壳及中冈底斯带110 Ma时地壳物质发生脱水重熔形成的则弄群酸性火山岩具有非常相似的蛛网图曲线,表明其可能为地壳物质脱水发生重熔有关?结合冈底斯带中北部地区广泛分布130~110 Ma则弄群?多尼组等火山岩分析,认为西藏申扎县买巴地区早白垩世110 Ma左右中?酸性侵入岩是班公湖—怒江洋盆南向俯冲消减的产物?
关键词:  关键词:早白垩世  U-Pb年龄  冈底斯带  石英二长岩  花岗岩  买巴
DOI:
分类号:
基金项目:中国地质调查局项目(1212011121257)和国家自然科学基金项目(41272091)联合资助?
Zircon U-Pb age and geochemistry of Early Cretaceous intrusive rocks in Maiba area of Xainza County, Tibet
ZHANG Yu-jie, LIUWei, ZHU Tong-xing, AN Xian-yin, LIAO Zhong-li1,2
1. Chengdu Center, China Geological Survey, Chengdu 610081, Sichuan, China;2. School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, Anhui, China
Abstract:
Abstract:In this paper, the authors studied the intrusive rocks widely distributed in Carboniferous - Permian strata in Maiba area of Xainza County within northern Middle Gangdise belt, and obtained the LA-ICP-MS zircon U-Pb age of 110.8±0.9 Ma for graniteand age of 111.0±1.1 Ma for quartz monzonite, respectively. Both ages are consistent within the error range, suggesting that the granite and the quartz monzonite should be the product of the same magmatic activity. The intrusive rocks are characterized by highSiO2, supersaturated aluminum (A/CNK=1.05-1.38), and enrichment of Al, Th, LREE, with Th abundance being 14.8×10-6-28.4×10–6, implying that they are probably associated with the upper crust substances. Their cobweb curve is remarkably similar to that of the upper crust and acidic volcanic rocks resulting from crustal remelting of 110 Ma Zenong Group in Middle Gangdise belt. These data indicate that the intrusive rocks might be the remelting products caused by the dehydration of crustal materials.
Key words:  Early Cretaceous  U-Pb age  Gangdise  quartz monzonite  granite  Maiba area