Previous Articles     Next Articles

Multi-wave Seismic Exploration Technology for Lithologic Gas Reservoirs of Low- Permeability Sandstone in Sulige Gas Field

Wang DaXing1,2Zhao Yuhua1,2Wang Yonggang1,2Zhang Mengbo1,2Cheng Sijian1,2   

  1. 1 National Engineering Laboratory of Low-permeability Oil and Gas Field Exploration and Developmen;2 Petroleum Exploration and Development Research Institute of PetroChina Changqing Oil?eld Company
  • Online:2015-03-15 Published:2015-05-21

Abstract: Sulige gas field is a typical low-permeability, low-pressure and low-abundance gas field in Ordos Basin. The sand bodies of the He-8 Member of the Lower Permian Shihezi Formation are vertically overlaid and horizontally linked up. The effective layers are relatively thin with the water-gas relations complicated. The technological research is focused on multi-wave seismic processing and fluid detection in the light of the above-stated issues. A number of key multi-wave processing technologies are emphasized in the study, such as static correction of conversion wave, velocity analysis, and P and S wave consistency processing, improving imaging precision of multi-wave seismic data. Meanwhile, multi-wave joint pre-stack simultaneous inversion, multi-wave AVO analysis, and rock elastic parameter crossplot are applied in a creative way to acquire more accurate elastic parameters and reduce the multi-description of reservoir prediction by use of only P wave. Based on crossplot of two independent elastic parameters to identify abnormal response, the resolution of reservoir is improved as compared to the prediction by using a single seismic parameter. As a result, the accuracy of lothologic and fluid detection is improved, enabling the coincidence rate of predicting effective reservoirs (referring to gas-bearing layers and accumulated thickness of gas-bearing layers) to exceed 80 percent. Remarkable achievements have been made in application of this technology for deployment of well location in exploration and development of Sulige Gas Field. It also provides a technological support for large-scale and effective development of the gas field.