ACOUSTIC CHARACTERISTICS OF HYDRATE-BEARING SEDIMENTS：A COMPARATIVE ANALYSIS OF EXPERIMENTAL AND NUMERICAL SIMULATIONS RESULTS

Acoustic characteristics of hydrate-bearing sediments are very important in hydrate exploration. So far, some important research progresses have been reached in experimental simulation and rock physics modeling. However, the numerical simulation based on experimental conditions and comparative studies between the above are still lacking. This paper intends to obtain the acoustic characteristics of hydrate reservoir through physical experiment simulation by combining laboratory physical simulation together with experimental reservoir numerical simulation. On the basis, a geological model is constructed based on the simulated experimental device model, and the reservoir velocity results obtained at the frequencies of 50 kHz and 80 Hz under different hydrate saturation conditions, and the wave field snapshots at different time points and saturation conditions are obtained. Comparative analysis of the similarities and differences are carried out between the results obtained by experimental simulation and numerical simulation. The research shows that the correlation between the wave velocity of the hydrate reservoir at different times obtained under the three simulation conditions is good. The numerical simulation results confirm the results of the laboratory simulation experiments, suggesting that it is feasible to carry out corresponding rock physical simulation experiments in laboratory. Comparing the results of experimental simulation and numerical simulation experiment with field detection data, there is a consistent change trend, indicating that the results of physical simulation experiment and numerical simulation have important guiding significance for field exploration data analysis.