汶川地震前成都台重力的高频扰动

汶川8.0级地震发生前48小时，距震中约37千米的成都地震台GS15型重力仪记录到了附有高频扰动的潮汐观测数据。对该仪器不同时段观测数据的比较表明：这种高频扰动主要来自外界因素的影响。对2008年32个热带气旋，以及5.0—7.0级地震的统计分析表明：与热带气旋对应出现的高频扰动比例高于地震震前出现的扰动,而且低等级的相似距离的热带气旋也能够产生类似扰动现象。由此判定，汶川地震前48小时成都地震台出现的重力高频扰动主要来自热带气旋的影响。

GRAVITY DISTURBANCE OF HIGH FREQUCNCY AT CHENGDU SEISMOSTATION BEFORE WENCHUAN Ms8.0 EARTHQUAKE

About 48 hours before the Wenchuan \%M\%s8.0 earthquake, significant gravity pulsation was observed at the Chengdu seismostation by using GS15 gravity meter. Comparing the earth tide data in different periods of time, it is demonstrated that the significant gravity pulsation are mainly affected by the external factors.32 tropical cyclones, the occurrence of \%M\%s≥6.0 in China and \%M\%s ≥7.0 in world were selected and statistically analyzed. It is shown that the rate of significant gravity pulsation during the occurrence of tropical cyclones is far more than those during before the occurrence of the earthquake, and the same gravity pulsation can be observed by even weaker tropical cyclones. So the significant gravity pulsation at the Chengdu seismostation is mainly affected from the tropical cyclones before the Wenchuan earthquake.