MT time series simulation based on constructed system function
Zhang Baoqiang1, Pei Jianxin1,2, Wang Qi3
1. College of Marine Geosciences, Ocean University of China, Qingdao, Shandong 266100, China; 2. Key Laboratory of Submarine Geosciences and Prospecting Techniques, Ministry of Education, Qingdao, Shandong 266100, China; 3. Guangzhou Marine Geological Survey, Guangzhou, Guangdong 510760, China
Abstract：For magnetotelluric (MT) method, an effective geophysical tool, data impedance estimation and noise elimination are key steps, which have great influence on the impedance characteristics.So it is necessary to test impedance estimation and subsequently signal processing in the time domain with simulated electromagnetic time series.Based on constructed system function, the magnetic field in the frequency domain is obtained by the discrete Fourier transform (DFT) of random sequence, and the electric field in the frequency domain is calculated with model impedance and simulated magne-tic field.Finally, the symmetry processing of complex conjugate is performed on the unilateral spectrum of electromagnetic field and the impedance sequence in the frequency domain, and the simulated time series of electromagnetic field is obtained with inverse fast Fourier transform (IFFT).Test results show that the proposed method can be used to simulate the time series of one-dimensional and two-dimensional horizontal heterogeneous model, and compared with measured data, the electromagnetic field data obtained with this method can better reflect MT frequency spectrum characteristics.
张宝强, 裴建新, 王启. 基于构造系统函数的大地电磁时间序列模拟方法[J]. 石油地球物理勘探, 2018, 53(2): 410-417.
Zhang Baoqiang, Pei Jianxin, Wang Qi. MT time series simulation based on constructed system function. Oil Geophysical Prospecting, 2018, 53(2): 410-417.
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