五台山新生代隆升剥露的磷灰石裂变径迹研究  

Apatite fission track study of Cenozoic uplifting and exhumation of Wutai Mountain, China

作　　者：庆建春[1] 季建清[1] 王金铎[1] 彭青兰[1] 牛向龙[2] 葛志宏[1] 

机构地区：[1]北京大学地球与空间科学学院,北京100871 [2]中国地震局地质研究所,北京100029

出　　处：《地球物理学报》2008年第2期384-392,共9页Chinese Journal of Geophysics

摘　　要：五台山是中国三级地貌重要分界线之一太行山脉海拔最高的山，其隆升历史的研究对中国三级地貌形成时代的确定具有重要意义．沿五台山最高峰北台顶向北自上而下至山根和阜平县境内长城岭地区海拔最高点向东自上而下至山根两条剖面，分别采集一系列岩石样品，最后挑选16个样品进行磷灰石裂变径迹研究．通过对封闭径迹长度分布直方图的分析，表明五台山样品自晚白垩纪末以来一直在单调冷却，即五台山在持续地隆升；通过对样品径迹年龄一高程图的分析，同时结合热史模拟及Excel数据拟合，表明晚白垩纪末以来五台山的隆升为分阶段幕式过程，共经历了三期快速隆升：74—58Ma、46～31Ma及15Ma左右．五台山晚白垩纪末以来的隆升与太行山其他地区及周边张宣隆起、泰山等其他山系的隆升在时间上存在对应关系，所以，五台山新生代隆升为区域性构造演化的一部分．Wutai Mountain is the highest mountain in Taihang Mountain-chain, which is one of the important boundaries of the three grade physiognomy in China. The study on its uplifting history is important in confirming the forming age of the three grade physiognomy. We collected a series of rock samples along two sections, one is from Beitai peak of Wutai Mountain northwards and downwards to its root, and the other is from the maximal altitude of Changchengling Region, Fuping county, eastwards and downwards to its root. Then we selected 16 samples to make apatite fission track study. The histogram of length distribution of the confined fission track shows that the samples in Wutai Mountain had been cooling monotonously since the end of late Cretaceous, i. e. Wutai Mountain had been uplifting since then. The analysis of the fission track age-height plot of samples, the inverse modeling of thermal history and Excel data fitting reveal that the uplifting of Wutai Mountain was episodic since the end of late Cretaceous, which included three rapid uplifting periods, 74 - 58 Ma, 46 - 31 Ma and about 15 Ma. The uplifting of Wutai Mountain since the end of late Cretaceous correspond with the uplifting of other regions in Taihang Mountain-chain and its peripheral mountains, such as Zhangxuan Uplift and TaishanMountain etc. in time,indicating Cenozoic uplifting of Wutai Mountain is a part of regional tectonic evolution.

关 键 词：五台山 新生代 隆升 裂变径迹 区域性构造演化 

分 类 号：P542[天文地球—构造地质学]