伽师近场地震资料处理——三维速度成像  

Data Processing of Nearfield Earthquake Records in Jiashi Earthquake Region——3-D Velocity Tomograthy

作　　者：赖晓玲[1] 张先康[1] 李松林[1] 

机构地区：[1]中国地震局地球物理勘探中心,郑州450002

出　　处：《中国科学院研究生院学报》2003年第1期50-55,共6页Journal of the Graduate School of the Chinese Academy of Sciences

基　　金：地震科学联合基金课题资助(10 2 0 2 5 )

摘　　要：利用三维速度结构和震源位置的联合反演方法,处理了伽师近场地震资料,得到强震区 2 0km以上深度的速度图像.结果表明:震区地壳内 8km以上速度结构横向非均匀性较强,反映了该区厚达数公里的沉积盖层介质特征;1 2～ 1 8km深度速度成像存在北东和北西的低速异常带,它们相交于极震区下方,反映了区域发震构造特征;沿极震区的东西和南北正交方向以及强震群分布的两侧,地壳结构均有明显差异。A joint inversion of 3 D velocity structure and hypocenter positions was used in Jiashi nearfield data processing. Velocity imaging over the depth of 20 km has been obtained. The results show that velocity structure over the depth of 8 km is strongly and horizontally heterogeneous. Characteristics of sedimentary cover of several kilometers in this region is revealed. Velocity imaging at 12～18 km depths shows two low velocity zones, one trending NE and the other NW. They intersect below the meizoseismal area, revealing characteristics of earthquake occurrence tectonics in this region. Obvious difference exist in crust structure along the EW and the SN direction in the meizoseismal area and on the two sides of the strong earthquake sequence zone. This is one of the deep backgrounds of strong earthquakes development.

关 键 词：资料处理 三维速度成像 近场地震资料 三维速度反演 伽师强震区 地壳结构 震源位置 地震观测 

分 类 号：P315.61[天文地球—地震学]