汶川MS8.0地震北川附近同震和震后垂直位移特征

Co- and post-seismic vertical displacements of Wenchuan MS8.0 earthquake near Beichuan

摘要: 利用北川附近震前水准数据，以及2008年和2010年两条一等水准数据, 得到了北川附近同震和震后垂直位移量, 获得如下结果: 北川附近的北川——映秀断裂的同震垂直位移量为4.711 m，断层上下盘最大位错量为5.1 m, 然而, 位于平武县境内的青川断裂同震位错仅有0.064 m. 2008——2010年, 汶川MS8.0地震后北川附近的北川——映秀断裂震后垂直位移速率为5——27 mm/a, 江油县大康镇附近的江油——广元断裂震后垂直位移速率为20.6 mm/a, 而古城区附近的青川断裂垂直位移速率仅为0.2——1.3 mm/a.

Abstract: Co- and post-seismic vertical displacements of the Wenchuan MS8.0 earthquake, derived from pre-seismic leveling data and two measurements in 2008 and 2010 along two first-order leveling lines near Beichuan, show the following features: Co-seismic displacement along Beichuan-Yingxiu fault was as large as 4.711 m near Beichuan, where the maximum observed fault offset was 5.1 m. In contrast, the observed co-seismic offset of the Qingchuan fault in Pingwu County was only 0.064 m. From 2008 to 2010, the post-seismic displacement rate was 5mdash;27 mm/a near Beichuan-Yingxiu fault in Beichuan area, 20.6 mm/a at Jiangyou-Guangyuan fault near Dakang, and only 0.2mdash;1.3 mm/a at Qingchuan fault near Gucheng.