Selection of Wavenumbers from SVD Analysis in CSEM 2.5D Modeling

All 2.5D modeling algorithms are employing Fourier transform along the strike direction. Most of 2.5D appreaches select a set of wavenumbers only by trial and error in order to obtain wavenumber domain responses. We propose a new way for selecting the minimum number of wavenumbers for the calculating of secondary electromagnetic fields. This method begins with a predefined set of wavenumbers to apply Fourier transform on primary fields from a HED, and then SVD analysis gives us am apparatus for selecting the minimum number of wavenumbers. Finally,resistivity and phases for a 2.5D model are calculated with these wavenumbers.