基于三维地质模型的地质储量不确定性分析——以西非尼日尔三角洲盆地P油藏为例

Uncertainty analysis of geological reserves based on 3D geological model ——A case study on P reservoir in Niger delta basin in the west Africa

为了合理评估地质储量、论述地质储量不确定性产生的原因,指出测量技术的局限性、已有数据的有限性和参数选取主观性是地质储量不确定性产生的主要原因;针对确定法和基于数学模型的概率法在地质参数不确定性和相关性方面的研究不足,研究了基于三维地质模型的油气地质储量不确定性评估方法;以西非尼日尔三角洲盆地P油藏为例,系统分析了油气藏地质储量评估中各地质因素的不确定性,指出顶面构造、砂体分布、流体界面、储层参数是影响地质储量计算结果的主要因素。这种基于三维地质模型的地质储量不确定性分析方法有效揭示了地质储量评估中的风险,为投资建议、井位部署和产能规划提供了科学决策的依据。

In order to properly evaluate the oil and gas volumes in place,the reasons for volume uncertainty are demonstrated.The technical limitation,data limitation and subjectively parameters selection listed as the main causes of volume uncertainty.Uncertainty analysis based on 3 D geological modelling are studied due to the uncertainty in the input data and inconsistency between them.The volume uncertainty analysis workflow is established and the geological parameters affecting volumes are summarized as top surface,sand distribution,fluid contacts,porosity,water saturation and volume factor based on the study in an oilfield of Niger delta basin.By taking P reservoir of Niger delta basin in west Africa as an example,the system analysis of the geological reserves evaluation of oil and gas reservoirs of the uncertainty of the geological factors is carried out,which points out the top surface structure and sand body distribution,fluid interface,reservoir parameters are the main factors affecting geological reserves calculation results.Uncertainty analysis of oil and gas volumes in place by using 3 D geological modeling method properly indicates the risks in volume estimation,which provides the basis for scientific decision in investment,well placement and production planning.