摘要
The high precision GPS measurement is an important method for studying the crustal movement and crustal deformation.On April 20,2013,an earthquake of MS7.0occurred in Lushan(30.3°N,103°E),south of Longmenshan faults.According to the monitoring station(BXB:30.48°N,102.71°E and BXN:30.26°N,102.84°E)data and based on GPS monitoring data inversion and analysis,it is inferred that the 4.20Lushan focal mechanism is a thrust-diastrophism type of earthquake.GPS monitoring results showed the co-seismic displacement as the follows:on the north side of the fault station BXB,the east component of the co-seismic displacement is 34.0mm,the north component of co-seismic displacement is-28.2 mm,and the vertical component of co-seismic displacement is +10.3 mm;on the south side of the fault station BXN,the east component of co-seismic displacement is-45.5 mm,the north component of co-seismic displacement is-25.9mm,and the vertical component of co-seismic displacement is-67.8mm.In the earthquake zone,the length from north to south was shortened by 3-6mm,the horizontal dislocation displacement is 78-82mm,and the vertical dislocation displacement is 75-80mm.