用于地震预警的三维实时定位方法

A 3D real-time evolutionary earthquake location for seismic early warning

为了尽快定位地震,在"着未着"定位算法基础上,尝试引入三维地壳模型,构建具有三维空间格点分布的走时表。根据已触发台站的到时和未触发台站的位置信息设计概率分布函数,通过八叉树搜索方法,快速给出震源在三维空间的可能位置。使用波前追踪算法,计算中国几个地区三维地壳模型的走时网格,利用中国地震台网资料,对区域内发生的地震进行定位分析。结果显示,在一定的台网密度条件下,三维实时定位方法能在震后数秒给出震源位置,可满足地震预警要求。

In this work, we try to introduce 3D crust model and construct traval time grids in 3D space to locate earthquakes rapidly and accurately based on the ＂trigger/non-trigger＂ location algorithm proposed by Horiuchi （2005）. The most probable location of hypocenter in 3D space is given quickly from triggered arrivals and not-yet-triggered stations by the Octree searching method. We calculate several travel time tables in 3D crust model in different areas of China, and then locate and analyze earthquake events happened in these areas with data from China Earthquake Net. The result shows that this 3D real-time evolutionary earthquake location method can locate the hypocenter in seconds after the earthquake happened, so it can be used for seismic early warning under a satisfactory density of stations distribution.