[关键词]
[摘要]
2010 年8 月4 日至2013 年10 月4 日福建仙游共记录到地震1209 次,其中最大地震为2013 年9 月4 日发生的ML5. 0 地震。为了加强对仙游地震序列的研究,更好地了解仙游地震的发震构造及震区的区域应力场,本文利用福建数字地震台网宽频带地震记录,采用矩张量反演方法,得到仙游地震序列中ML > 3. 5 的6 次地震的震源机制解。这6 次地震的震源机制解结果较为一致,都为走滑型地震,断层走向为NW 向,倾角陡立,主压应力轴方向为近SN 向。反演得到的主压应力轴方向与福建地区的区域应力场并不一致,本文认为仙游地震是由位于震区的金钟水库蓄水造成震区应力调整而引起的。
[Key word]
[Abstract]
The 1209 earthquakes occurred in Xianyou,Fujian from August 4,2010 to October 4,2013. The largest earthquakes is ML5. 0 on September 4,2013. To strengthen the research of Xianyou earthquake sequence and understand the causative structure and stress field of Xianyou, the focal mechanism solutions of six earthquakes (ML > 3. 5) in Xianyou are calculated using the broadband digital data of Fujian Earthquake Network and the seismic moment tensor inverse method. The results show that the focal faults of the 6 earthquakes are similar. They are all strike slip faults with the fault strike to the northwest and high dip angle. The principal compressive stress axes are near to SN,which are different of the stress field of Fujian region. The Xianyou earthquake sequence may be induced by the stress adjustment after the impoundment of Jinzhong reservoir.
[中图分类号]
[基金项目]
中国地震局地震科技星火计划(XH12026Y)资助