松辽盆地林深3井火山岩的锆石U-Pb年龄与Hf同位素组成
Zircon U-Pb ages and Hf isotopic composition of volcanic rocks from Well Linshen 3 in Songliao Basin
金鑫 1葛文春 1薛云飞 2金玉东2
作者信息
- 1. 吉林大学地球科学学院,长春,130061
- 2. 大庆油田有限责任公司勘探开发研究院,黑龙江,大庆,163712
- 折叠
摘要
根据松辽盆地北部林深3井火山岩的岩相、全岩主微量元素、锆石U-Pb同位素和锆石Hf同位素特征的分析结果,探讨了该火山岩的形成时代和岩浆源区.锆石LA-MC-ICPMS U-Pb研究结果表明:林深3井火山岩形成时代约为120 Ma,处于早白垩世中晚期,属于营城组火山岩.锆石的LAMC-ICPMS Hf同位素研究显示,本区火山岩的锆石εHf(t)全部为较高的正值,二阶段Hf模式年龄为789～1 494 Ma,表明其主要起源于中-新元古代增生的地壳物质,暗示中-新元古代时期兴蒙造山带东段存在地壳增生事件.
Abstract
The formation time and the source rocks of volcanic rocks from Well Linshen 3 in the northern Songliao Basin have been discussed through the petrography, major and trace elements, zircon U-Pb isotopic data and zircon Hf isotopic data of three samples.Zircon U-Pb dating by LA-ICP MS technique indicated that the volcanic rocks from Well Linshen 3 were erupted at ca.120 Ma, the middle-late Early Cretaceous, belonging to of the Yingcheng Formation.Zircon Hf analysis conducted by LA-MC-ICPMS showed that all of the volcanic rocks had high εHf(t) positive values with Hf modal ages of 789 ～ 1 494 Ma, indicating the crust in the Songliao Basin extracted from mantle during Meso- and Neoproterozoic, which provides the important evidence of crustal growth during Meso- and Neoproterozoic in eastern Xing-Meng orogenic belt.
关键词
松辽盆地/林深3井/火山岩/锆石U-Pb年龄/Hf同位素Key words
Songliao Basin/Well Linshen 3/volcanic rocks/zircon U-Pb age/Hf isotope引用本文复制引用
基金项目
国家自然科学基金(90814003)
国家自然科学基金(40739905)
出版年
2011
NETL
NSTL
万方数据