环渤海湾盆地主要河流碎屑锆石U-Pb年龄特征及其物源示踪意义

在环渤海湾盆地的汇入河流碎屑沉积中寻找理想的物源示踪指标，对理解和认识渤海湾盆地以及中国东部陆架海的物质扩散均具有重要意义。利用激光剥蚀电感耦合等离子质谱仪（LA-ICP-MS）对渤海湾盆地周缘主要河流的碎屑锆石进行微区原位U-Pb年龄分析，对比前人已经报道的研究结果，发现辽河和滦河同时接受中亚造山带和燕山山脉的物质供给，永定河、滹沱河和漳河的物质分别来自燕山和太行山。黄河汇集了上游的祁连山、秦岭和黄土高原以及华北克拉通南部的物质信号。渤海湾盆地南部的鲁中山区和胶东半岛的碎屑锆石峰值年龄组成与燕山、太行山、黄河流域存在显著差异。因而，利用碎屑锆石U-Pb年龄特征能很好地区分近源的滦河、永定河、滹沱河、漳河、大清河、胶莱河和远源黄河的物质信号。

U-Pb age characteristics of major fluvial detrital zircons in the Bohai Bay Basin and their provenance implications

It is of great significance to select ideal provenance indices for the in-flowing detrital sediments into the Bohai Bay Basin for further understanding the material diffusion process on the continental shelf of East China.In this paper,the LA-ICP-MS is used to analyze the in situ U-Pb age of detrital zircons from major rivers around Bohai Bay.Combined with the previous research results,our data suggest that the Liaohe and Luanhe rivers are both supplied by the sediments from the Central Asian Orogenic Belt and the Yanshan Mountain.The sediments of the Yongding,Hutuo and Zhanghe rivers mainly come from the Yanshan mountain and Taihang mountain respectively.The peak age compositions of detrital zircons in the Luzhong Uplift and Jiaodong Peninsula are significantly different from those from the Yanshan,and Taihang mountains and the Yellow River drainage.Our results demonstrate that the U-Pb age of the detrital zircons is an efficient mean to distinguish the sources of detrital sediments from the rivers surrounding the Bohai Bay Basin.