Characterization of well water level dynamics due to volcanic movements in Tonga
In order to identify and extract the characteristics of well water level changes caused by the Tonga volcanic eruption on 15 January 2022,four observation wells in the Tangshan area of Hebei Province were used as the study object,and the well water level and barometric pressure observation data were processed separately using the EEMD method,and the signals characterized by the observation data were classified into a number of IMF components from high to low frequency. Through the high-frequency components to describe the change characteristics of well water level and air pressure high-frequency events,combined with the Hilbert spectral analysis to obtain the two high-frequency event energy fluctuations in the frequency band range is the same,the occurrence of the time is similar,and further coherence analysis. The results show that after the Tonga volcano earthquake erupted,there were two changes in the well water level,and the trend of the water level waveform changed synchronously and inversely with the barometric pressure waveform,and the results of the coherence indicate that the well water level is significantly correlated with the barometric pressure,and that the Lindsay mine is more responsive to the drastic changes in the barometric pressure. On this basis,the efficacy of the EEMD method for short time series well water level processing is analyzed and the ability of the Hilbert spectrum to identify disturbing signals in well water levels is explored.
volcanic earthquake in TongaEEMDHilbert spectral analysiswell water level and air pressure
万方数据
维普
