Confirmation of AVO Attribute Inversion Methods for Gas Hydrate Characteristics Using Drilling Results from the Shenhu Area, South China Sea

Amplitude versus offset (AVO) attribute inversion can help to constrain lithologies and interpret oil and gas accumulations. In this paper, we simulate four different gas hydrate and free gas configurations through AVO forward modeling. When there is no free gas under gas hydrate, the AVO attribute characteristics of gas hydrate are only related to the saturation of gas hydrate. When there is free gas under gas hydrate, if the gas hydrate saturation is high, the AVO attribute characteristics [such as the product of intercept (P) and gradient (G)] are not sensitive to identify gas hydrate. Otherwise, the AVO attribute characteristics are sensitive for identifying gas hydrate, but greatly affected by free gas. The results of this paper constrain the distribution of gas hydrate in the Shenhu area and provide a basis for future gas hydrate exploration.