On 20 April 2013, an Mw 6.6 earthquake struck Lushan, Sichuan province, China (hereafter as Lushan earthquake), which caused 196 deaths and 21 missing. As another disastrous earthquake occurred on the Longmenshan fault after the 2008 Mw 7.9 Wenchuan earthquake, the Lushan earthquake stimulated an extensive discussion about its seismogenesis. In particular, whether it was a large aftershock of the 2008 Mw 7.9 Wenchuan earthquake has been heatedly debated (Chen et al., 2013; Du et al., 2013; Liu, Yi, et al., 2013; Wang et al., 2013; Jia et al., 2014). Actually, after the Wenchuan earthquake, an increased seismic hazard for the southwest of the Longmenshan fault has been commonly recognized (Parsons et al., 2008; Toda et al., 2008). The occurrence of the Lushan earthquake seems to have confirmed this common understanding, and further attracts attention on the re‐evaluation of future seismic activities on the southwest Longmenshan fault (Chen et al., 2013). As the basis of these discussions, the source characteristics of the Lushan earthquake need to be well understood.

As a routine work for fast source earthquake information, Zhang et al. (2013) released the preliminary teleseismic rupture model about three hours after the Lushan earthquake. Their results show that the earthquake has no dominant rupture direction. The major slip area is located around the hypocenter and does not reach the surface.

It is known, however, that teleseismic data can only constrain the ruptured area relatively to the hypocenter (rupture initiation point). In contrast, near‐field strong‐motion data can provide information useful in precisely and accurately locating …