Abstract:Based on the array data of Rushan, using the double-difference accurate location method, this article clarifies the sequence distribution of aftershocks occurring in Rushan, Shandong Province, since May 2014. We then invert the three-dimensional velocity model with double-difference tomography method. The data reveals that the aftershocks in Rushan generally gather circularly with a predominance distribution of 3-8 km nearby; the aftershocks of Rushan earthquake swarms occur mainly in rupture-concentrated regions, with most at the depth of 5 km, which proves that Rushan earthquake swarms happened primarily at the upper crust. The P-wave velocity at different depths in the researched regions show dramatic changes. Because of the certain distance from the already-known main faults, it can be estimated that aftershock-concentrated regions are the branch fault of Rushan or a new buried fault here.