油气储层相控随机建模技术的约束方法

Stochastic modeling for characteristics of petroleum reservoir constrained by facies

提出根据相控随机建模技术描述油气储层特征,并用已知地质数据和沉积微相的研究成果,如平面展布方向、宽厚比等来指导相控建模,文章提出“多层分级控制,同级套合管理”的相控随机建模策略,并将相序、概率、定量知识库或变差函数三个方面相结合来表征油气储层的非均质特性。具体则是从沉积形成与演化的成因角度指导沉积储层随机建模的过程,应用多参数协同、分层次约束的方法,运用沉积相带的平面展布和垂向演化来控制建模的结果,并用宝力格油田的实际地质和钻井数据验证优选得到的多个模型实现。结果表明:优选模型真实地反映了地下油气储层的非均质特性和连通性展布特征,并经新钻井数据验证确实有效。

We present a stochastic modeling for characteristics of petroleum reservoirs constrained by facies to yield results coincided with real geological setting. The facies acting as the constraint are based on known geological data and include depositional microfacies such as an extension direction and a ratio of width to thickness of microfacies. A strategy of the reservoir modeling controlled by facies is as follows： scale differences of reservoir controlled by hierarchy for multi-depth levels along vertical direction; for each depth level, plane zone differences of reservoir managed with nested structure. The constraints are exerted by the following three aspects： combining the order of facies, probability correlation and quantitative geological knowledge database or variogram to constrain heterogeneities of petroleum reservoir. The modeling constrained by facies is characterized by depositional formation and genetic evolution used for as guidance of the modeling, use of coordination of multi-parameter and constraint by hierarchy, full use of horizontal distribution and vertical evolvement of depositional facies belts as constraint boundary. The geological and drilling data in Baolige oil fields in Inner Mongolia, North China are used to check and optimize the method. Results show this optimized modeling can indicate heterogeneity and connectivity distribution of subsurface reservoirs, and have been confirmed by new wells in Baolige oil fields.