Research and Application of Joint Interpretation Using P-Wave and PS-Wave in Tight Gas Exploration

Abstract

The exploration and development of tight sandstone gas reservoirs are controlled by high-quality river channel sand bodies on a large scale in Sichuan Basin. In order to improve the accuracy of sand body prediction and characterization, Multi-component exploration technology research has been carried out in Northwest Sichuan Basin. First, based on the array acoustic logging data, a forward modeling has been established to analyze the seismic response characteristics of the PS-wave data and P-wave data. The result shows that the response characteristics of the P-wave and PS-wave to the sand bodies with different impedance are different. And then through the analysis of logging data, the effectiveness of the forward modeling has been proved. When the sandstone velocity is close to the surrounding rocks, the P-wave performs as a weak reflection, which may lead to reduce the identification range of the sand bodies. However, the PS-wave exhibits strong reflection, which can identify this type of sand bodies. Finally, by comparing and explaining the PS-wave data and P-wave data, and integrating their attributes, the prediction accuracy of sand bodies is improved. Compared with the interpretation of a single P-wave, the results can significantly expand the distribution range of sand bodies, laying a foundation for improving the production capacity of single wells and reserve submission.

Keywords

multi-component exploration / tight gas / sand body identification

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