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塔藏断裂位于东昆仑断裂带东段,属于“玛曲空区”范围,汶川M_S8.0级地震对该区域造成了应力的加载,但是本区尚未开展古地震方面研究,地震危险性认识不足。通过断错地貌实测、古地震探槽、~(14)C定年等方法,在坡中谷、断塞塘附近位置开挖两处探槽,获得了一些古地震方面的认识。探槽附近微地貌测量结果表明,断错量主要分布在两个范围区间72m和71m,以及27m,25和22m,两区间之间近倍数关系,推测由多次地震事件造成。两处探槽采集~(14)C样品共计19个,探槽剖面分别记录了2次古地震事件,事件发生的层位与年龄具有一定的可比性,经逐次限定后得到2次古地震事件,时间分别为320±30～500±30aB.P.和2730±30～2840±30aB.P.;最近一次古地震离逝时间为320±30～500±30aB.P.;实际重复间隔约为2300a,与东昆仑断裂玛曲段的重复间隔较为接近。
The Tazian fault is located in the eastern section of the East Kunlun fault zone and belongs to the range of “Maqu space”. The Wenchuan M_S8.0 earthquake caused stress loading in this area. However, the study on paleoseismicity has not been carried out in this area and seismic hazard Lack of understanding By means of fault landform survey, paleoseismic exploration, ~ (14) C dating and other methods, two exploration trenches were excavated in the vicinity of Slope Valley and Piedai Pond, obtaining some understanding of paleoearthquakes. Micro-geomorphological measurements near the trenches show that the amount of fault distrubution is mainly distributed in the 72m and 71m of the two ranges, and the near multiple of 27m, 25 and 22m, which is estimated to be caused by multiple earthquakes. A total of 19 samples of ~ (14) C were collected from the two trenches, and two paleoseismic events were recorded on the trenches section respectively. The occurrences of the layers were comparable to those of the ages. Two successive earthquakes , The time was 320 ± 30 ~ 500 ± 30aB.P. And 2730 ± 30 ~ 2840 ± 30aB.P .; The time of the last paleo-earthquake was 320 ± 30 ~ 500 ± 30aB.P .; The actual repetition interval was about 2300a, and the interval of Maqu segment of East Kunlun fault is relatively close.