Modeling and numerical simulation for coupled flow and geomechanics in composite gas hydrate deposits

We investigated composite gas hydrate deposits where the fine scale single porosity model for geomechanics was difficult to apply. To this end, the multiple porosity model was used for the composite reservoirs, upscaling geomechanics but keeping the fine scale for flow. We analyzed the numerical results of the multiple porosity model, comparing them with the reference solutions, the fine scale single porosity system. From the comparison, the multiple porosity model successfully approximated the reference model, providing good accuracy for pressure, saturation, effective stress, and subsidence fields and reducing geomechanical computation. In particular, when geomechanical properties of an upscaled gridblock were the same as those of its subelements, the results of flow and geomechanics between the reference and multiple porosity models were almost identical. Thus, the multiple porosity model can be useful for composite gas hydrate reservoirs. Copyright 2012 ARMA, American Rock Mechanics Association.

Modeling and numerical simulation for coupled flow and geomechanics in composite gas hydrate deposits Conference Paper