浅水三角洲分流河道三维储层建模方法比较

Comparison of the Reservoir Stochastic Modeling Methods for the Underwater Distributary Channels in Shallow Water Delta

以中国西部某油田长8油组浅水三角洲分流河道为例,分别采用序贯指示建模和多点地质统计学方法对分流河道进行表征。从模拟结果看,多点地质统计学方法较好地再现了河道形态特征,建立的河道连续性好,与实际河道具有可比性;而序贯指示建模方法建立的河道较为零散,河道三维形态相对较差。从11个模拟实现计算的储量看,两种方法的储量均值较为接近,但多点地质统计模拟的储量变动范围小,方差也小,反映了多点统计模拟方法整体差异性小于序贯指示建模。方法比较结果表明,多点地质统计学模拟实现的不确定性小,更适合油田开发与决策。

The underwater distributary channels in shallow water delta are simulated by using the sequential indicator simulation method and multiple-point geostatistics simulation method in Chang 8 Formation of an oilfield in West China, respectively. The simulation results show that the multiple-point geostatistics simulation method reproduces the channel geometries and continuities, but the sequential indicator simulation method realization is of much more ＂noise＂ and discontinuities. Eleven realizations are constructed and the reservoir volumes are calculated using both methods with the average volumes close to each other, but the delta and deviation of the volumes of single normal equation simulation method is much smaller, which reveals that the uncertainty of multiple-point geostatistics simulation method is less than sequential indicator simulation method. So the multiple-point geostatistics simulation method contributes better to oilfield development.