Parametric Magnetotelluric Impedance Tensor Estimation

Conventional magnetotelluric (MT) impedance tensor estimation methods are generally based on robust M-estimator spectral analysis along with remote reference (RR) processing to reduce the estimation biases caused by cultural noise. Here, we propose a parametric spectral estimation and system identification-based impedance tensor estimation method and validate it with three representative data segments measured at several USArray sites. The proposed parametric method has the potential to give an accurate and robust estimate of the electromagnetic transfer impedance without an RR while maintaining a smooth and continuous response in accordance with prior physical knowledge. The approach considers the geophysical problem in addition to signal processing and system identification, providing a statistically efficient strategy for electromagnetic transfer impedance estimation of periods from 10 to 10
⁴
s.