Abstract：When AVO analysis and inversion are applied to reservoir prediction and fluid detection,the various seismic attribute value ranges need to be defined simultaneously to effectively characterize the reservoir distribution.However,Poisson impedance(PI) attribute sually acts as an indicator of oil and gas.That means the single PI attribute can be used to realize reservoir characterization,and obviously eliminate the affection of compaction background trend.After a joint study of rock physics,PI curve calculated from logging data and seismic combined with logging,we have accomplished the reservoir prediction of an interesting zone in the Block H of the West Africa coastal basin.The following observations are obtained: ① Reservoir prediction and fluid detection will be failed only with P-wave impedance,or S-wave impedance,or P and S wave velocity ratio,or Poisson ratio respectively.② The PI threshold values for different formation lithology do not change at any depth.So the affection of compaction background trend can be eliminated,and the PI attribute can be effectively used to identify lithology or hydrocarbon.The oil sands PI range is less than 1250g/cm3·m/s,and the water-saturated sands PI range is between 1250g/cm3·m/s and 1600g/cm3·m/s,but the mudstone PI range is more than 1600g/cm3·m/s.③ The PI value keeps a negative correlation relationship with oil saturation.Using PI attribute,both the interesting exploration targets and their distribution in the Block H are defined.
