Key Points and Current Studies on Seepage Theories of Marine Natural Gas Hydrate-Bearing Sediments: A Narrative Review

The internal fluid flow capacity of hydrate-bearing sediment (HBS) is one the important factors affecting efficiency natural gas exploitation. This paper focuses on seepage studies hydrates with following contents: scope theories’ application, normalized permeability (Kt) models, extension combined new technology, and development. No review has elucidated prediction original (K0) sediments without hydrates. Moreover, there are few theories technologies, such as Computed Tomography (CT), Nuclear Magnetic Resonance (NMR), Imaging (MRI), resistivity. However, this summarizes prospects, evolution, application HBS from perspectives experiments, numerical simulation, microscopic visualization. Finally, we discuss current limitations directions HBS.