基于孔隙旋回建模单元的碳酸盐岩储层建模研究

Research on carbonate reservoir matrix model building based on porosity cycles

储层建模涉及到多种技术,任何一项技术的改进都会对模型精度产生影响。碳酸盐岩储层在形成过程中经历成岩、构造等作用,使储层变得复杂、非均质,但对于孔隙层、溶洞层由张开裂缝连通的似块状储渗体构架碳酸盐岩储层来说,孔隙层和溶洞层的分布具有规律性和旋回性。该文以四川盆地某气藏为例,提出基于孔隙度旋回作为建模单元建立碳酸盐岩储层基质地质模型,以达到提高储层模型精度的目的,即寻找孔隙度曲线上的变化规律,划分孔隙度旋回,然后以孔隙度旋回为建模单元,采用确定性建模和随机建模相结合的方法建立碳酸盐岩储层基质模型,有效地提高储层模型精度。

Reservoir modeling refers to many technologies,and the improvements on any of which will affect model accuracy.Despite that digenesis and tectonic factors have made carbonate reservoirs become complicated and heterogeneous,for pore or cave layer carbonate reservoirs connected by extensional fractures,the distribution of pore or cave layers has regularity and cyclicity.Taking a gas reservoir in the Sichuan Basin as an example,porosity cycle is put forward as a model unit to build up carbonate reservoir matrix geological model.Porosity cycles are divided based on the change law of porosity curves.Then with these porosity cycles,combining deterministic modeling with stochastic simulation,carbonate reservoir matrix geological model is developed to increase reservoir modeling precision.