SEGJ Technical Conference

The adaptive techniques for magnetoterullic survey in the area dominating coherent noise. -2- A technique for the estimation of impedance valiance utilizing magnetic fields at the remote reference site

Abstract We modified the conventional method to estimate the valiances of magnetotelluric impedance to be effective method for the data contaminated with strong coherent noise. The conventional method uses the difference between observed electric field and predicted electric field from observed magnetic data, as substitutes for the electric field error that is required for estimation of the valiances. However, the method estimates the valiance at small value against the strong coherent noise. In order to solve the problem, we substituted the referenced magnetic data for the observed magnetic data to estimate the predicted electric field. Using the modified method for the synthetic data and field data, we could get the results that indicate the effectiveness against the strong coherent noise. Besides, using both conventional method and our method, it is indicated that we can evaluate the suspicious for the bias effect on the magnetotelluric sounding curves.