摘要
An Mw9.0 earthquake occurred on March 11, 2011 offshore the coast of Miyagi Prefecture of Honshu, Japan. In this paper, based on GPS coseismic displacement field and characteristics of error we invert for the distribution of coseismic dislocation. The result of error analysis shows that the coseismic displacement within 300 km in NW, 550 km in north, and 700 km in SW direction is significantly larger than the error, so can provide effective constraints to the inversion of surface displacement. The north-west section of GPS observation and inversion results show that near-field coseismic displacement is characterized by exponential decay withdistance. Dislocation inversion results show that the largest coseismic dislocation is 25. 8 m, located near the epicenter. Dislocation greater than 10 m occurr mainly within 400 km near the epicenter, the southern section of the Japan Trench has relatively smaller coseismic dislocation. According to the spatial distribution of seismic rupture, combined with previous earthquake rupture distribution of the region, the Mw9.0 earthquake rupture embodies the characteristics of in situ recurrence, but also reflects the nature of earthquake rupture filling in the blank.