Estimation of the gas hydrate saturation in the South China Sea

摘要

As a potential energy resource, gas hydrate has been widely concerned by researchers around the world. Accurate estimation of hydrate saturation is essential for hydrate studies, and it is difficult in the case of fracture-filled gas hydrate. In order to obtain a better estimation of hydrate saturation, we improve the conventional inversion method by considering the fracture dip angles varying with depth for fracture-filled gas hydrate bearing sediments (GHBS). We apply different rock physical models to simulate pore- and fracture-filled GHBS in the Dongsha area of the South China Sea. Then we obtain the saturations of these two types of gas hydrate at different sites. The results are basically in agreement with the measured saturations based on Cl~- concentrations. This method is proved to be effective in the study area, and moreover, it provides a more comprehensive perspective to calculate fracture-filled hydrate saturation.