Relocation of the 2016 M_S6.4 Menyuan, Qinghai earthquake

The rupture initiation point and hypocentoid of Menyuan M_S6.4 earthquake, which occurred on January 21, 2016, were imaged out by means of time-reversal imaging technique (TRIT) using velocity models and waveforms from regional seismic network and China Seismic Array. The results show that, origin time of Menyuan M_S6.4 earthquake was 01:13:11 on January 21, 2016 and rupture initiation point was at (37.67°N, 101.61°E), and the focal depth was 9.41 km. The migration of hypocentroid can be divided into two stages of 1--6 s and 7--10 s, which basically located at an inclined plane dipping to NE with an inclination about 75°. According to the characteristic of hypocentroid migration, we speculate that the nodal plane with strike of 335°, dip of 56° and rake of 97° is the rupture plane of Menyuan earthquake. Considering large rake angle, Menyuan earthquake shows characteristic of thrust tectonic activities with high dip angle, so we are likely to convince that Menyuan earthquake resulted from new activity of north Lenglongling secondary thrust fault with high dip angle.