山西大同与晋中盆地全新世活动断裂定量研究中热释光与^(14)C测年方法应用  

THERMOLUMINESCENCE AND CARBON-14 DATING METHODS APPLIED TO QUANTITATIVE STUDIES OF THE HOLOCENE ACTIVE FAULTS IN DATONG AND JINZHONG BASINS, SHANXI

作　　者：江娃利[1] 王焕贞[1] 

机构地区：[1]中国地震局地壳应力研究所,北京100085

出　　处：《第四纪研究》2004年第3期332-340,共9页Quaternary Sciences

基　　金：地震科学联合基金重点项目 (批准号 :2 0 10 17)资助;中国地震局地壳应力研究所论著号 :2 0 0 3A0 15

摘　　要：文章通过对山西断陷系内 4条边界活动断裂带开展全新世活动定量研究中实测的 6 7个热释光测年样品及 2 0个1 4C测年样品的实例分析 ,讨论了在断错地貌研究和探槽全新世古地震研究中 ,地层测年样品帮助确定断层活动事件年代、判断探槽内古地震事件的时间跨度、古地震事件的完整性及垂直断距的不确定性等方面发挥的作用 ;并讨论了少量热释光样品出现年代倒置现象的原因。In order to dating Holocene paleoearthquakes, 67 samples for Thermoluminescence (TL) and 20 samples for 14 C were used. Samples were taken near the active faults including the Kouquan fault and the northern piedmont fault of Mt. Hengshan on the western and southern boundary of Datong basin, and the Taigu fault and the Jiaocheng fault on the eastern and western boundary of Jinzhong basin respectively. The important role of 14 C and TL dating in determining the age of dislocated geomorphology and paleo-earthquake was discusses. In the geomorphological investigation 28 TL samples and 3 14 C samples were dated. Among them, 8 TL-samples were taken from the back-border of alluvial fans; 7 TL samples from the bottom of gullies and the first and second order terraces; 13 TL-samples from the front and back border of loess platform. 3 14 C samples were taken from loam layers in the first order terrace on upthrown wall of the fault. Only three TL ages contradict with others, and therefore not used. The dating results indicate that the upper deposits at the alluvial fans back-borders on the downthrow side of the faults in Datong basin formed during Middle Holocene. While the strata at the foot of the upthrown side along the newest dislocated faces of the Taigu and Jiaocheng fault can be dated to Early Holocene. Therefore, the ages of deposits proved that the multiple activities on the Kouquan fault and on the northern piedmont fault of Mt. Hengshan took place along the main fault planes in between bedrock and back margin of alluvial fans. It also proved that the fault planes of Jiaocheng fault and partial segments of the Taigu fault are distributed as step faults. The newest activities of the faults migrate towards the basin. Ten big trenches have been opened along the four faults in the research. Our study on these trenches, showed that fourteen strong earthquakes took place along the four faults during Holocene, four on the Kouquan and Taigu fault and three on the northern piedmont f

关 键 词：热释光与^14C 测年 全新世 活动断裂 山西断陷系 

分 类 号：P315.2[天文地球—地震学] P542[天文地球—固体地球物理学]