Abstract：Geologic,drill and seismic data have different characteristics and exactitudes;therefore,we use Cokriging method in predicting reservoir geophysical parameters by comprehensively analysing these data. It is a multivariable geostatistical analysis method that estimates optimal,linear and unbiased interpolation values. Under unbiased condition,we can minimize Cokriging variance to estimate Cokriging equations system. Then,covariance and cross-covariance are computed by using variogram so as to consider the direction,range and variation degree of geologic structures. In order to calculate variogram .two feasible schemes and five models are adopted to remove the problems in calculation which arise from insufficient boreholes. Moreover,by self-adaptation method,we select some very important variables from multitudinous seismic parameters to reduce computation and to improve prediction effect.the method was used to predict the lateral variation of porosity,permeability and oil saturation in Wen-51 fault block in Pucbeng oil field,resulting in satisfactory effect.
