Gas-bearing property prediction of Leikoupo Formation in the northwest Sichuan Basin based on the theory of two-phase media

The Leikoupo Formation in northwest Sichuan Basin has great potential in exploration,quite a few wells demonstrate active oil and gas showings during drilling,and good gas-bearing property and reservoir development are interpreted from well logging.Aiming at tackling the unclear distribution of favorable gas-bearing zones of Leikoupo Formation and based on the combination of seismic geological conditions and well logging data,the authors conducted Empirical Mode Decomposition processing to compensate high-frequency energy while preserving the low-frequency energy,which laid the data basis for subsequent bi-media hydrocarbon detection technique.Then amplitude spectrums at different well locations were compared and analyzed,the low-frequency energy enhancement and high-frequency energy attenuation were found where reservoir contained gas.With the optimized frequency range,hydrocarbon detection based on two-phase media theory was implemented on the seismic data of the study area.The results of hydrocarbon detection are well consistent with the data from drilling wells and the geological law,which confirms the validity of proposed techniques and provides the directions for expanding oil and gas exploration range and area of Leikoupo Formation in northwest Sichuan Basin.