MAGNETOTELLURIC THREE-DIMENSIONAL MODELING USING THE STAGGERED-GRID FINITE DIFFERENCE METHOD

The crucial problems of 3 T5BZ]D forward modeling using the staggered-grid finite difference method are described in detail in this paper. They are staggered-grid, discretization of integrated form of Maxwell equation, boundary condition, solving linear algebra equations and calculating D forward modeling using the staggered-grid finite difference method are described in detail in this paper. They are staggered-grid, discretization of integrated form of Maxwell equation, boundary condition, solving linear algebra equations and calculating 3 T5BZ]D tensor impedance. Giving the more explicit boundary conditions and using Bi-conjugate gradients stabilized method to solve the linear algebra equation with large coefficient matrix, we get a fast algorithm of high-precision to calculate effectively electrical and magnetic fields in the whole space. This has been proved by comparing the 3D forward modeling solutions with analytic solution to abutting quarter-spaces, and 2D forward modeling to 2D prism using the 2D finite element method. This efficient algorithm has setup basis for research of D tensor impedance. Giving the more explicit boundary conditions and using Bi-conjugate gradients stabilized method to solve the linear algebra equation with large coefficient matrix, we get a fast algorithm of high-precision to calculate effectively electrical and magnetic fields in the whole space. This has been proved by comparing the 3D forward modeling solutions with analytic solution to abutting quarter-spaces, and 2D forward modeling to 2D prism using the 2D finite element method. This efficient algorithm has setup basis for research of 3D inversion .