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介绍了用远震P波背投影法得到的2009年4月6日拉奎拉MW6.3级地震的破裂详情。该方法此前用于大级别的地震,而此次是首次用于中等尺度的地震。我们处理了从美国地震学联合研究协会(IRIS)数据中心获得的60个宽带台站的垂向分量地震图。利用多通道互相关算法对记录迹线进行了排列及归一化处理,并运用第四次根叠加进行破裂成像。我们发现,拉奎拉地震破裂方向为南向,第2次的能量离散脉冲于标称发震时刻之后约17～18s发生在震中以东20～25km处。从图像上看,破裂的空间范围与该地区震后对破坏的测量结果非常吻合。由于该方法进行破裂成像速度快(破裂图像在发震时刻后20～30min便可得到),因此,可以将其用于政府机构的应急响应及救援工作中。
The details of the rupture of the L’Aquila MW6. 3 earthquake on April 6, 2009, which were obtained by teleseismic P-wave back projection method, are introduced. This method was previously used for large-scale earthquakes, this time for the first time for moderate-scale earthquakes. We processed the vertical component seismograms from 60 broadband stations obtained from the American Seismological Association (IRIS) data center. The recording traces were arranged and normalized using the multi-channel cross-correlation algorithm, and the fourth root overlay was used for fracture imaging. We find that the direction of the earthquake in L’Aquila is southward, and that the second discrete energy pulse occurs about 20 ~ 25km east of the epicenter about 17 ~ 18s after the nominal epicentral time. Judging from the image, the spatial extent of the rupture is in good agreement with the measurement of the damage caused by the earthquake in the area. Due to its high speed of rupture imaging (rupture images are available 20 to 30 minutes after the onset of the earthquake), it can be used in emergency response and rescue efforts by government agencies.