ANALYSIS OF PERTURBATION PHENOMENA OF DEFORMATION DATA IN SHANXI PROVINCE
陕西形变资料扰动现象分析

Through analyzing deformation data in Shanxi province,perturbations frequently appeared before M≥4 earthquake in range of 400 km or M≥5 earthquake in range of 500 km.It is shown in two aspects: 1)response of vertical pendulum in Hanzhong seismostation,water tube tiltmeter at Qianxian station and Xi’an station,vertical pendulum at Ningshan station to large aftershocks of Wenchuan Ms8.0 earthquake,2)response of vertical pendulum at Qianxian station to Hejing Ms4.8 earthquake.