摘要
对微震信号的初至时刻的拾取是对微震分析的关键,在现场采集到的微震信号中往往含有大量的噪声,会造成对信号初至时刻的识别误差。基于STA/LTA算法、AIC算法和数字滤波器、小波去噪以及EMD分解去噪等相关降噪方法对含噪信号的拾取效果进行了分析,提出了在不同信噪比的环境下拾取初至时刻的最优算法,对于信噪比大于30 dB的信号可以直接计算初至时刻;对于信噪比在10~20 dB的信号可以使用降噪后的信号来拾取初至时刻;对于信噪比小于10 dB的信号可以使用降噪后的信号与AIC法相结合来拾取初至时刻。同时,根据现场采集到的不同信噪比的微震数据对初至时刻拾取,拾取结果较直接使用单一方法识别精度有所提升。
Picking up the first arrival time of the microseismic signal is the key to the microseismic analysis.The microseismic signal collected in the field often contains a lot of noise,which will cause the identification error of the first arrival time of the signal.Based on STA/LTA algorithm,AIC algorithm,digital filter,wavelet denoising and EMD decomposition denoising,the picking effect of noisy signals is analyzed,and an optimal algorithm for picking up first arrival time under different SNR environments is proposed.The first arrival time can be calculated directly for signals whose SNR is greater than 30 dB,and for signals with SNR of 10 to 20 dB,the signal after noise reduction can be used to pick up the first arrival time.For the signal whose signal-to-noise ratio is less than 10 dB,the denoised signal can be combined with AIC method to pick up the first arrival time.At the same time,according to the microseismic data with different signal-to-noise ratio collected in the field,the first arrival time is picked up,and the recognition accuracy of the picking result is higher than that of using a single method directly.
作者
钱鼎
贺志杰
宋义敏
苑德顺
QIAN Ding;HE Zhi-jie;SONG Yi-min;YUAN De-shun(School of Civil Engineering,Northern University of Technology,Beijing 100144,China)
出处
《煤炭技术》
CAS
北大核心
2021年第12期119-125,共7页
Coal Technology
基金
国家自然科学基金项目(401053761806)。
