The characteristics of continuous gravity changes in Qiongzhong seismic station
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摘要: 收集了2009年以来琼中地震台(以下简称琼中台)连续重力观测数据,经对原始数据进行突跳、台阶和删除错误数据等处理,计算分析了琼中台重力潮汐变化数据特征、M2波潮汐因子变化特征和典型事件的观测数据频谱特征。结果表明,琼中台连续重力观测数据除包含了固体潮、零漂等长周期信号外,也记录到了地震和台风等高频信号。对于记录到的7.0级以上强震,地震信号的频率主要分布于0.3 Hz以内;台风引起的扰动信号则主要分布于0.1—0.4 Hz频带内。同时,2009年以来,琼中台连续重力原始数据及其M2波潮汐因子无明显前兆异常。Abstract: This paper collected the continuous gravity observation data from Qiongzhong seismic station since 2009. After processing the raw data with sudden jumps, steps and error data, we calculated and analyzed the characteristics of the gravity tide data from Qiongzhong seismic station, the characteristics of the M2 wave tide factor and the spectrum characteristics of the observation data of typical events. The results show that the continuous gravity observation data of Qiongzhong seismic station include not only long-period signals such as solid tide and zero drift, but also high-frequency signals such as earthquakes and typhoons. For the recorded strong earthquakes above 7.0, the frequency of seismic signals is mainly distributed within 0.3 Hz; the disturbance signal caused by the typhoon is mainly distributed in the 0.1—0.4 Hz frequency band; at the same time, the original continuous gravity data of Qiongzhong seismic station and its M2 wave tide factor have no obvious precursory anomalie since 2009.
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Key words:
- continuous gravity /
- annual variation /
- M2 wave tidal factor /
- frequency spectrum /
- earthquake
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表 1 PET重力仪主要技术指标
Table 1. The main specifications of PET gravimeter
主要技术指标 参数 分辨率 0.01×10−8 m•s−2 精度 1.0×10−8 m•s−2 频率范围 1 s至无穷长 仪器零漂率 小于300×10−8 m•s−2/月 -
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