蒙宁交界地区测震台站环境背景噪声特征分析OA

Seismic environmental background noise is caused by multiple sources across specific frequency bands.Quantifying environmental background noise can help evaluate the quality of stations'observations.Based on the continuous waveform data recorded by six seismic stations in the border area of Nei Mongol and Ningxia from January 1 to March 31,2024,the background noise characteristics and noise diurnal variation of seismic stations in the study area are analyzed and studied by calculating RMS,PSD,and PDF distributions,and the influence of human activities on background noise is determined.The results show that RMS values at all seismic stations exhibit a diurnal variation,with low values during the daytime and high values at night in the frequency band of 1-20 Hz.The background noise levels at Zhongwei,Bayanhot,Shizuishan,and Wuhai seismic stations are relatively high due to varying degrees of human disturbance;Yinchuan and Wujiahe seismic stations have good windbreak and heat-preservation effects,and the surrounding human activities are few,so the background noise level is relatively low.The high-frequency noise of seismic stations is mainly affected by human activities.The seismic stations located in industrial areas,urban peripheries,and mine areas have relatively high noise levels in the high-frequency band,and these levels vary greatly day and night.In agricultural,mountainous,and less-populated areas with little human and industrial activity,station background noise levels are low,and daily variation is small.