一种定量评价储集层地质模型不确定性的方法

A quantitative method for appraising reservoir geological model uncertainty

针对目前国内储集层地质模型不确定性评价中存在的问题,提出了以地质储量和可驱替储量为定量指标的三维储集层地质模型不确定性定量评价方法。储集层地质模型的不确定性源于建模本身和储量计算两方面,着重分析了相建模中的不确定性因素。采用实验设计抽取了一组地质概念模型描述储集层地质特征的所有可能,定量分析了不确定性因素对模拟结果的影响,掌握了主要不确定性因素的统计特征。以主要不确定性因素-储量的多项式响应曲面代替建模过程,采用蒙特卡罗法计算了储量概率分布,评价了储量风险。综合考虑储量规模、储集层连通性和发生概率,提供给油藏数值模拟一组优选的模型实现。

To improve the uncertainty appraisement of reservoir geological models, a quantitative appraisement method, using OOIP and drainable OOIP as the indexes and based on 3-D stochastic reservoir modeling, is put forward. Uncertainties of reservoir models exist in the process of modeling and in the calculation of reserves, and the uncertainties in facies modeling are focused on. Based on the modeling realizations of geological models which are singled out by experiments and designed to describe the likelihoods of reservoir characteristics, the effects of uncertainty factors on the modeling are estimated quantitatively and the statistic features of the main factors are figured out. Using the multinomial response surface of the main uncertainty factors and reserves as the substitute for modeling, probabilistic reserves are calculated by Monte Carlo method. Taking into account of reserve scale, reservoir connectivity and probability, a set of optimized realizations are provided to numerical reservoir simulation.