Probable productive formations are recognized by log data standardization

log curve automativc layering and establishing recognizing models; the parmeters such as effective porosity of The formaions

the absofute and effectivePermeabilities of gas

the index and the coefficient of productivity

and the comprehensive index are calculated. The sedata are used as evaluation porters to detendne pwhctive formations. The standard model of productivity gradecan be obtained by cluster analysis

sublayer productivity grad could be connected to the reservoir productivity(testnonresistance out flow)

and then the evaluation and the prediction of reservoir productivity could be realized.