琼中地震台PET重力仪和CTS-1EF地震计记录的热带气旋信号特征分析

Analysis of characteristics of the tropical cyclonic signal recorded by the PET gravimeter and the CTS-1EF seismometer at Qiongzhong Seismic Station

收集了琼中地震台PET重力仪和CTS-1EF地震计在“威马逊”“海鸥”“莎莉嘉”等3个热带气旋影响期间的观测数据,通过计算获得速度和加速度。比较了热带气旋接近和远离琼中地震台时,重力仪、地震计记录的波形特征,并通过频谱、时频对比,分析重力仪和地震计数据受热带气旋影响的程度。结果表明,在热带气旋影响期间,2台仪器记录数据的速度与加速度具有较好的一致性,均有明显扰动,波形形态基本一致。但PET重力仪的最大扰动幅度均小于CTS-1EF地震计,热带气旋的信号主频段为0.15—0.25 Hz。

Observed data from PET gravimeter and CTS-1EF seismometer of the Qiongzhong Seismic Station during the three tropical cyclone which were“Weimason”,“Seagull”and“Sally Jia”activitied were collected to calculate the velocity and acceleration values,respectively.The influence of tropical cyclone on the observed data of gravimeter and seismometer were analyzed through comparing the calculated speed and acceleration waveforms of the two instruments and their spectral characteristics during the tropical cyclone closing or going away from the Qiongzhong Seismic Station.The results illustrate that the velocity and the acceleration recorded by the two instruments are in good agreement,and they both produce significant disturbances.However,the maximum amplitude of the PET gravimeter is smaller than that of the CTS-1EF seismometer.The main frequency band of the tropical cyclone signal is 0.15-0.25 Hz.