Numerical Modeling of Gas Hydrate Recycling in Complex Media: Implications for Gas Migration Through Strongly Anisotropic Layers

Abstract Burial driven recycling is an important process in the natural gas hydrate (GH) systems worldwide, characterized by complex multiphysics interactions like migration through evolving stability zone (GHSZ), competing gas‐water‐hydrate (i.e., fluid‐fluid‐solid) phase transitions, locally appearing and disappearing phases, sediment properties (e.g., permeability, reaction surface area, capillary entry pressure). Such a typically studied homogeneous or layered sediments. However, there mounting evidence that structural heterogeneity anisotropy linked to normal inclined fault anomalous layers have strong impact on GH dynamics. Here, we consider impacts of such structurally media process. To capture accurately, introduce fully mass conservative, high‐order, discontinuous Galerkin (DG) finite element based numerical scheme. Moreover, handle rapidly switching thermodynamic states robustly, cast problem transitions as set variational inequalities, combine our DG discretization scheme with semi‐smooth Newton solver. present new simulator, demonstrate using synthetic geological scenarios, (a) how presence high‐permeability layer, fracture brecciated sediment, can alter flow‐localization, more importantly, (b) incorrect incomplete approximation layer lead large errors overall prediction