综合地质、钻井和地震资料预测储层物性参数

由于地质、钻井和地震资料的性质及精度不同，因此在综合利用上述资料预测储层物性参数时，本文采用了协克里金法。此法是一种多变量地质统计学方法，也是一种求最优、线性、无偏内插估计量的方法。即在无偏条件下使协克里金方差达到最小，从而得到协克里金方程组，然后通过变异函数计算变量的协方差和互协方差，以便考虑地质结构的方向性、变化范围以及变化程度。为此，在求变异函数时，本文提出了两种可行方案，使用了5个变异函数模型，从而克服了井少时计算变异函数的困难。另外，用自适应方法从众多的地震参数中提取作用较大的变量，以减少计算量，提高预测的效果。文中用此法预测濮城油田文51断块的孔隙率、渗透率和含油饱和度的平面变化，均取得了满意的效果。

Predicting reservoir physical parameters by comprehensively analysing geologic, drill and seismic data

Geologic,drill and seismic data have different characteristics and exactitudes;therefore,we use Cokriging method in predicting reservoir geophysical parametersby comprehensively analysing these data. It is a multivariable geostatistical analysismethod that estirnates optimal,linear and unbiased interpolation values. Under unbi-ased condition,we can minimize Cokriging variance to estimate Cokriging equationssystern. Then,covariance and cross~covariance are computed by using variogram soas to consider the direction,range and variation degree of geologic structures. In or-der to calculate variogram. two feasible schemes and five models are adopted to re-move the problems in calculation which arise from insufficient boreholes. Moreover,by self-adaptation method,we select some very important variables from multitudi-nous seismic parameters to reduce computation and to improve prediction effect-The method was used to predict the lateral variation of porosity,permeabilityand oil saturation in Wen-5l fault block in Pucheng oil field,resulting in satisfacto-ry effect.