In order to improve the accuracy of log interpretation and the applicability of interpretation model for zones

the suitable porosity and saturation models are established for analysis of the 3rd member of Funing Formation in the west slope of Qintong sag

North Jiangsu basin. After the statistics and analysis of the experimental porosity and well logs

it is found that interval transit time after shale correction and the porosity of the experimental analysis can satisfy the relation among acoustic formation factors. The interval transit time for the rock matrix in this area is determined to be 189.39 μs/m

the matrix lithology coefficient（

x

） is 1.472

and the interpretation model f

or the porosity in the zone is established. And then

the relation between formation factor（

F

） and porosity is analyzed. Meanwhile

the variation rule of cementation index（

m

） with core porosity is determined

that is

with the increase of porosity in mesoporous reservoirs

m

is relatively stable

while with the increase of porosity in high-extra-high pore reservoirs

m

tends to increase. Therefore

the variable cementation index（

m

） can be calculated from well logs

and then the oil saturation of reservoir can be calculated accurately. The interpretation results of the established porosity and saturation models in this area agree well with the experimental analysis.