中国东北～500Ma泛非期孔兹岩带的确定及其意义
Confirming of the Heilongjiang-500Ma Pan-African khondalite belt and its tectonic implications
周建波 1张兴洲 1Simon A WILDE 2郑常青1
作者信息
- 1. 吉林大学地球科学学院,长春,130061
- 2. 吉林大学地球科学学院,长春,130061;Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, WA 6845
- 折叠
摘要
东北地区的变质基底,如佳木斯地块的麻山群、兴安地块的兴华渡口群等岩石组合是以(含石墨)大理岩、夕线石榴片麻岩、斜长角闪岩等为主要标志的孔兹岩系.在额尔古纳、兴安和佳木斯-兴凯地块的夕线石榴片麻岩分别得到锆石U-Pb 年铃,证明这些高级变质岩的原岩年龄以新元古代(600～850Ma)为主,变质年龄为～500Ma,因此东北地区的变质基底记录了从Rodinia到Gondwana大陆的聚合与离散的过程.泛非期高级变质岩及其同期岩浆岩在额尔古纳、兴安、松辽、佳木斯和兴凯地块等断续分布,总体出露范围>1300km,并沿虎头、鸡西、萝北、兴华渡口和漠河一线总体北西向沿黑龙江断续分布,因此我们命名为"中国东北泛非期孔兹岩带"."中国东北泛非期孔兹岩带"的提出和进一步研究,对深入探讨东北地区各地块基底组成的异同性以及陆块聚合的过程,以及东北地区的构造演化历史及其在Gondwana大陆重建中的位!都具有重要的科学意义.
Abstract
The basement rocks in NE China, including Mushan Croup in Jiamusi Block, Xinghuadukou Group in the Xing' an Block, constitute a khondalitic sequence of sillimanite- and garnet-bearing gneisses, homblende-plagioclase gneiss and felsic paragneisses. Zircon U-Pb dating of the garnet-sillimanite gneiss samples from Erguna, Xing' an and Khanka blocks indicates high-grade metamorphism occurred at ～500Ma, where several detrital zircon grains whose ages extend between 600Ma to 850Ma The Pan-African high-grade metamorphism with magmatism events were obtained from all the blocks in NE China, including the Erguna, Xing' an, Songliao and Jiamusi-Khanka blocks, establish a over 1300km Pan-African khondalite belt in NE China, named here the ' Northeast China Khondalite Belt'. The results from this study provide new idea for researching the tectonic affinity and plate evolution in the NE China.
关键词
孔兹岩带/泛非期/原岩年龄/变质年龄/高级变质岩/中国东北Key words
Khondalitic belt/Pan-African/Protholith age/Metamorphic age/High-grade metamorphic rocks/NE China引用本文复制引用
基金项目
国家自然科学基金(40739905)
国家自然科学基金(40872121)
国家重点基础研究发展规划(973计划)(2009CB825008)
出版年
2011
NETL
NSTL
维普
万方数据