Seismic wave attenuation in hydrate-bearing sediments based on the patchy saturation model in the Shenhu area, South China Sea

Abstract

In the Shenhu area, South China Sea, a study on P-wave attenuation in the hydrate-bearing sediments has been developed based on the Biot-Squirt (BISQ) porous medium model. However, the BISQ model has been proven to be inappropriate for the attenuation characteristics at seismic frequencies. We have adopted the patchy-saturation model, which is being increasingly considered to be more suitable for attenuation analysis at seismic frequencies in porous media, to study P-wave attenuation in the hydrate-bearing sediments in the Shenhu area, South China Sea. The theoretical modeling indicates that the P-wave attenuation at seismic frequencies is observed to decrease when the sediments contain gas hydrates. In the case studies in the Shenhu area, the interval inverse [Formula: see text]-factors from seismic reflection data were estimated, and the results indicate good agreement with the theoretical modeling.

Recent advances in theory and technology of oil and gas geophysics

“…Zuoxiu He, from the Chinese University of Petroleum-Beijing, delivered a presentation entitled "Rock physics modeling and AVO forward modeling for gas-hydrate reservoir in South China Sea". In his work, rock physics models suitable for hydrate-bearing reservoir in South China Sea were selected to carry out rock physics modeling (Li and Liu, 2017), and the frequency-dependent AVO (amplitude versus offset) forward modeling was carried out to obtain synthetic seismogram with attenuation (Guo et al, 2015), which was then compared with real seismogram and synthetic seismogram of convolution model. The rock physics modeling shows that the gas hydrate in South China Sea is most likely to be cemented or loadbearing hydrate.…”