概率体约束地质建模在西湖凹陷X气田的应用

摘要

Modeling of tight gas reservoir in less well area on the sea is one of problems which are eager to overcome.Aiming at solving high heterogeneity of tight sandstone gas reservoirs in braided river deposits, it is difficult to accurately characterize reservoir''s distribution of "sweet point" and properties using conventional geological modeling method.In this paper, using "sweet point" controlling, multiple-point geo-statistics and probabilistic volume constraint on thick layer reservoirs in the East China Sea, we have innovatively modeled using "sweet point" in a form of facies and generated training image in different ways considering different kinds of "sweet point" and simulated facies based on Poisson''s ratio volume and "sweet point" probabilistic volume as a second constraint.The results show that simulating "sweet point" in the form of facies by using multiple-point can overcome limitation of single facies and characterize the spatial structure of "sweet point".The result is in line with geological knowledge by using different training images in different members.The prediction accuracy of distribution of "sweet point" has been improved under the constraint of probabilistic volume.%针对辫状河沉积致密砂岩气藏的强非均质性特点,常规地质建模方法难以准确表征储层"甜点"分布及属性预测.以东海西湖凹陷X气田为例,采用"甜点"相控、多点地质统计、概率体约束方法,将"甜点"以相的形式进行相控建模,针对不同类型"甜点"采用不同方法生成训练图像,并以泊松比数据体和"甜点"概率体为第二约束完成多点相模拟.结果表明,将"甜点"以相的形式进行多点相模拟能克服单一相控的局限并有效表征出"甜点"的空间结构,分段采用不同训练图像模拟的"甜点"符合地质认识,在概率体约束下"甜点"分布预测的精度得到提高.