1-D Forward Modeling for Marine CSEM Using Wavelets

Numerical solution to field governing equation of marine Controlled Source Electromagnetic (CSEM) geophysical surveys are commonly obtained using either finite element (FE) method or finite difference (FD) method. However, over the last couple of years, the use of wavelet method in finding numerical solution to field governing equation in various engineering applications has received great attention from researchers. The wavelet method has the advantage of providing more accurate solution then the FD and FE methods. In this paper, FD, FE and wavelet based numerical methods are implemented to solve field governing equation of CSEM geophysical survey. The results were obtained for both isotropic and homogeneous region and compared with analytical solution. It shows that for 1D isotropic region, the wavelet method results are closest in approximation to the analytical solution than the FD and FE. In particular, the wavelet method without multi-resolution analysis algorithm provides small errorof 10-4 whereas the FD and FE gave error of 10−3 and 10−3, respectively. With better accuracy, the wavelet method is expectedto provide more accurate and stable solution for inversion of marine CSEM geophysical survey data.