Hybrid Grid-Characteristic Schemes for Arctic Seismic Problems.

The process of conducting seismic exploration of gas fields with a source and receivers installed on the surface of an ice island is considered. A model that includes an ice formation, water area, multilayer geological massif, and a methane reservoir is built. The dynamic behavior of individual media is described using the theory of linear elasticity, acoustic equations, Maxwell's viscoelastic model, and Kukudzhanov's viscoelastoplastic model. The governing system of equations is solved numerically by applying the grid-characteristic method on rectangular meshes. Physical contact conditions between the media are set explicitly. A new hybrid scheme of higher order accuracy is constructed using a grid-characteristic monotonicity criterion. The scheme is used to obtain a full-wave solution of a two-dimensional seismic problem. [ABSTRACT FROM AUTHOR]