Direct gas-bearing Prediction of Carbonate Using Multi-wave Seismic Attributes

Aiming at the problem of gas prediction in deep carbonate formation, based on the high-precision matched PP and PS data, selecting typical wells with different gas-bearing characteristics, further carrying out the analysis of well logging data, seismic response comparison of PP wave and PS wave and the study of seismic forward modeling, we have a more reliable understanding on the PP and PS response characteristics of different gas-bearing conditions. That is, with the gas production decreasing from high to low, the reflection amplitude of PP wave gradually weaken, while that of PS wave change little and nearly have no obvious abnormalities. Finally, attributes of amplitude ratio and frequency ratio of the multi-wave were extracted for gas prediction, and the prediction results well distinguished between high-quality gas and poor gas layer, also in good agreement with the gas production characteristics of known wells, and this provides a direct, convenient and reliable gas prediction method in carbonate formations.