Gravity disturbances of Tai’an seismic station

This paper analyzed the tidal gravity data of Tai’an seismic station by using filtering method. The result showed that high frequency disturbances can be frequently observed on the background of the earth tide by the gravimeter. Compared with the records of meteorological observation, it was indicated that these disturbances were not only affected by the tropical cyclone such as typhoons, but also had relations with the strong regional convection weather such as cold wave transit. The further analyses on the data recorded at JCZ-1 ultra broad-band seismometer, by using frequency spectrum and filtering method, showed that the strong regional convection and typhoon have influence on gravimeter in the range of 1—8 s, and more obvious within 2—6 s. The distur-bance signal triggered by the strong convection weather process can be in the range of 1—16 s, but the gravimeter observation is almost not affected beyond 8 s, namely, there is a stopage period of gravimeter’s responding to the high frequency disturbance. The filtering result from the data recorded by JCZ-1 ultra broad-band seismometer also presented a dynamic characteristic of the disturbances, that is to say, during the developing and transmitting process of disturbances resulted from strong convection weather, high frequency signals firstly appeared, then gradually turned to the low-frequency ones with time, indicating the Doppler effect of the disturbance signal propagation, and the moving characteristics of inspiring source of the disturbance signals.