基于四阶互累积量的fast ICA微地震数据噪声

Recordings of microseismic and conventional seismic data are usually not synchronized.This interferes with the suppression of microseismic signals using the Fast Independent Component Analysis (Fast ICA) algorithm,resulting in an unwanted suppression of the signal.To overcome this issue,the fourth-order mutual cumulant algorithm is introduced to eliminate the time difference,and then the Fast ICA algorithm is applied to the blind source separation of microseismic data.In the paper,the fourth-order mutual cumulants and the Fast ICA algorithm are discussed first,and the accuracy of the time difference estimation by the fourth-order mutual cumulants is tested against simulated microseismic data.Then,the signal is migrated according to the estimated time difference.Finally,the Fast ICA blind source separation is carried out on the microseismic data after migration,so that a correct noise suppression can be performed,which is not affected by unwanted signal suppression.The test results showed that the fourth-order mutual cumulants can estimate the time difference with good accuracy.The results of the application to actual microseismic data demonstrated that the proposed method can denoise the signal well,without unwanted signal suppression.