Effect of Permeability on Hydrate-Bearing Sediment Productivity and Stability in Ulleung Basin, East Sea, South Korea

Methane hydrate has attracted attention as a next-generation resource, and many researchers have conducted various studies to estimate its productivity. Numerical simulation is the optimal method for estimating methane gas productivity. Meanwhile, using a reasonable input parameter is essential for obtaining accurate numerical modeling results. Permeability is a geotechnical property that exhibits the greatest impact on productivity. The permeability of hydrate-bearing sediment varies based on the sediment pore structure and hydrate saturation. In this study, an empirical permeability model was derived from experimental data using soil specimens from the Ulleung Basin, and the model was applied in numerical analysis to evaluate the sediment gas productivity and ground stability. The gas productivity and stability of hydrate-bearing sediments were compared by applying a widely used permeability model and the proposed model to a numerical model. Additionally, a parametric study was performed to examine the effects of initial hydrate saturation on the sediment gas productivity and stability. There were significant differences in the productivity and stability analysis results according to the proposed permeability model. Therefore, it was found that for accurate numerical analysis, a regional permeability model should be applied.

Automated summary

The study investigated the impact of permeability on gas productivity and stability of hydrate-bearing sediments, establishing an empirical permeability model from experimental data and comparing the application of different models in numerical analysis. The findings highlighted significant differences in productivity and stability analysis results based on the proposed permeability model, emphasizing the importance of using a regional permeability model for accurate numerical analysis.