Abstract:We use the convolution filtering method to eliminate rainfall correction processing for the resistivity of Shandan ground, and then carry out seismic response efficiency statistics on the original data and the data after rainfall removal respectively through the combination of different processing methods before the normalized monthly rate analysis, so as to select the optimal data processing method before the normalized rate analysis. The results show that the NS channel is suitable for decanting and deperiodic processing. Both EW and NW channels are suitable for deperiodic processing, and the seismic performance of each channel after the removal of rainfall is better than that before, indicating that rainfall has a great interference effect on the extraction of resistivity anomalies of Shandan station. Since the Qilian mountain seismic zone showed an unprecedented level of activity in 2022 and gradually recovered to a calm level in August, we select the rate overlimit anomaly of Shandan resistivity before moderate strong seismic activity in the Qilian mountain seismic zone and its vicinity from 2014 to 2022 to summarize the seismic response index. We predict the seismic risk of the gradually quiet Qilian mountain seismic belt by using the rate overlimit anomaly of the Shandan resistivity from August to December, and determine whether the seismic activity level near the Shandan observation station is really reduced. The results show that the rate overlimit anomaly still exists in the Shandan resistivity, which indicates that the seismic risk still exists in the Qilian mountain seismic zone and the seismic activity level has not weakened.
LI Na,FENG Jiangang,GAO Shude et al. Analysis of the Abnormal Characteristics of Shandan Resistivity Normalization Rate Based on Convolution Filtering[J]. jgg, 2023, 43(9): 950-956.