地质建模在X73油区长3油藏的应用

Geological modeling analysis of Chang 3 reservoir in X73 oilfield

X73油区位于鄂尔多斯盆地,是典型的低渗透油藏,具有非均质性强、低孔低渗、岩性致密以及孔隙结构复杂等特点,对油藏的高效注水开发产生了很大制约作用。因此结合新井资料,亟需对该油藏的非均质性等地质特征进行进一步综合研究。通过使用Petrel软件分别建立了研究区的地质构造模型、以泥质含量为变量而衍生的岩相模型以及基于岩相控制的属性模型,并通过物性参数的频率分布直方图来验证模型的准确性。结果表明,该研究区有效储层主要集中分布在西北部、中部以及西南部区域,以低孔隙度、低渗透率为主,这两个物性参数的展布方向为北向和北西-南西向。地质构造整体较为平缓,有两个利于原油富集的鼻状构造发育;同时,研究区各砂层组厚度稳定,整体呈片状分布,分布连续且面积较大。

Located in the Ordos Basin,the X73 oil area is a typical low-permeability reservoir with strong inhomogeneity,low porosity and low permeability,dense lithology and complex pore structure,which has a great constraint on the efficient water injection development of the reservoir.Therefore,it is urgent to further investigate the geological characteristics of this reservoir,such as inhomogeneity,by combining the new well data.By using Petrel software,the geological structure model of the study area,the petrographic model derived from the mud content as a variable and the attribute model based on the petrographic control were established respectively,and the accuracy of the model was verified by the frequency distribution histogram of the physical parameters.The results show that the effective reservoirs in the study area are mainly distributed in the northwest,central and southwest areas,with low porosity and low permeability,and the spreading directions of these two physical parameters are northward and northwest-southwest.The overall geological structure is relatively gentle,and there are two nose-like structures that are favorable for crude oil enrichment.At the same time,the thickness of each sand formation in the study area is stable,and the overall distribution is piecewise,continuous and large.