摘要
本文利用裂变径迹年代学方法 ,结合其他同位素年代学资料 ,通过构造热演化的定量分析 ,认为医巫闾山山脉的隆升历史经历了 118～ 81Ma期间的第 1个快速隆升阶段、81～ 14Ma期间的缓慢隆升阶段和 14Ma以来的第 2个快速隆升阶段。医巫闾山的隆升历史与两侧盆地的沉降历史有着很好的对应关系。山脉隆升相对盆地沉降有一个滞后期 ,山脉的快速隆升阶段对应盆地快速沉降的后期和消亡阶段。现今的医巫闾山山脉是 14Ma以来第 2个快速隆升阶段的产物 ,其隆起时间距今大约有 4～ 5Ma。
Thermal chronological evolutional curves were constructed for analyzing the uplift history of the Yiwulushan Mountains on the basis of zircon and apatite fission track dating combined with K Ar age data and U Pb age data of the Yiwulushan granite. The results show that there have been two periods of rapid uplift since the intrusion of the Yiwulushan granite. The first occurred from 118 to 81 Ma. The second has lasted from 14 Ma till now. The ancient Yiwulushan Mountains were slowly eroded from 81 to 14 Ma. The uplift history of the Yiwulushan Mountains has a good corresponding relationship with the depression history of the basins in the west and in the east. There is a delaying period in the mountain uplift relative to the depression of the basins. The rapid uplift of the mountains corresponds to the withering period of the basin or the late stage of the rapid depression of the basin. The present Yiwulushan mountains were formed in the second rapid uplift period, hence younger than 4～5 Ma.
基金
地矿部"九五"重点科技项目!<燕山造山带造山作用过程及动力学机制>的阶段性成果之一
