Abstract:Using cross analysis of impedance and Poisson to describe different rock and fluid type becomes common-used study method day by day.The paper tried to use the attribute of Poisson impedance for oil/gas detection.The Poisson impedance is defined as multiplication of Poisson velocity and density,the former is relative to P-and S-wave velocity of seismic waves(or Poisson ratio),and Poisson impedance integrates the feature of two attributes: Poisson ratio and density,which has special superiority in detection of gas-bearing sandstone.The results of application in PH9 well of Pinghu Oil/Gas Field showed that the constructed Poisson impedance raises the ability identifying water-bearing sandstone and gas-bearing sandstone in lower part of Pinghu Formation;meanwhile,on the basis of elastic impedance inversion,preliminary discussion on the ability identifying the gas-bearing strata on the profile by Poisson impedance achieved clear effect.