陕西石泉井不同频带水位对气压和固体潮的响应特征

为揭示陕西石泉井不同频带水位对气压和固体潮的响应特征，采用频谱分析、相干函数和时移分析方法，对石泉井2015-11-01~2016-02-29的井水位、气压和理论重力固体潮等进行深入分析。结果表明，低频带（f＜0.5 cpd）井水位对气压响应较为一般且波动较大，对固体潮响应很差；中频带（0.5~8 cpd）井水位对固体潮响应很好，同时，对气压成分中的K1、S2和S3频点有较好的响应；高频带（f＞8 cpd）井水位与气压和固体潮的相干性均较差，这可能由于该频带井水位的信噪比较低和气压能量较弱等因素所致。此外，在全频带内，随着气压周期的增大，井水位的滞后时间也相应从1 min增至720 min；在中低频带的某些频点或频段，井水位对气压响应的时移存在超前和异常波动现象。
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Response Characteristics of Water Level to Atmospheric Loading and Solid Earth Tide in Different Frequency Bands: A Case Study of the Shiquan Well,Shaanxi

The main objective of this research is to investigate the response characteristics of water level to atmospheric loading and solid Earth tide in different frequency bands in the Shiquan well, Shaanxi. Using the recorded water level, barometric pressure and the corresponding theoretical gravity tide from 1 November 2015 to 29 February 2016, we obtain the barometric and tidal responses of the water level by fast Fourier transform (FFT), coherence function, as well as cross-correlation. The results show that barometric response is relatively weak and fluctuates greatly, and the tidal response is extremely weak in low frequency band (f＜0.5 cpd); in the intermediate frequency band (0.5－8 cpd), tidal response is excellent; furthermore, the barometric responses are relatively strong at the frequency of K1, S2, and S3 waves, while the barometric and tidal responses are both relatively weak. The coherence functions between the water level and the barometric pressure are relatively low in high frequency (f＞8 cpd), reflecting a bad correlation between the two signals, which may be caused by the low signal-to-noise ratio in the water level and the relatively weak barometric signals. Moreover, the time lag of barometric response increases from 1 minute to 720 minutes with increasing periods of barometric pressure over all frequency bands. Lead effects and anomalous fluctuations appear in barometric response at some frequency points or ranges over medium-low frequency bands.