Abstract:In the paper "A statistical method used for predicting rich hydrocarbon zones" by Gao Ruzeng(《OGP》,No.4,1984),it is thought that fuzzy information statistics seem to be more suitable for describing the characteristics of seismic informations; however, this method is not convenient to use because its operation process is too tedious.On the basis of data from 38 sample wells supplied by Gao Ruzeng, a new mathematic model for integrative appraising a hydrocarbon prolific zone is developed using 6 kinds of Wparameter, namely, structure position, curvature, gas-reservoir-bottom amplitude ratio, instantaneous phase,instantaneous frequency, apparent polarity and gas-reservoir-top amplitude ratio.The program package consists of two programs; the program for calculating the frequency and optimum weight distribution values from sample data, and the predicting program.The operation process is simple and convenient.In making fuzzy integrative appraisement, the key to reliable prediction lies in determining good weight distribution values. Good weight distribution values can be found by gradually shortening the step size in search.The first step size should be neither too big nor too small, the reasonable one being 0.3-0.4.