礁滩型碳酸盐岩储层建模方法研究——以塔中62井区为例

Study on modeling method of reef-shoal carbonate reservoir——By taking Tazhong 62 well area as an example

礁滩型碳酸盐岩储层非均质性强,礁滩复合体储层井间预测难度大,难以建立精度较高的地质模型。针对礁滩型碳酸盐岩储层的特点,以塔中62井区为例,提出了"组合微相"的概念,利用地震相解释,采用确定性建模的方法,建立"组合微相"模型,以"组合微相"为约束条件,把能够反映储层变化的波阻抗作为次级变量,应用随机建模的方法建立孔隙度模型。由于裂缝对渗透率影响较大,应首先建立裂缝分布模型,以裂缝分布模型作为次级变量建立渗透率模型,从而提高渗透率模型的实用性。

The reservoir heterogeneity of reef-shoal type carbonate rocks is strong, and it is difficult to predict the reef-bank complex reservoirs between wells, and the difficulty on the establishment of geological models is big. According to the characteristics of reef-shoal carbonate reservoir, taking Tazhong 62 well area as an example, the concept of "composite microfacies" is proposed. By using seismic facies interpretation and deterministic modeling method, the "composite microfacies" model is established. Using the "composite microfacies" as control condition, the wave impedance which can reflect the change of reservoir is taken as secondary variable, and the porosity is established by using the method of stochastic modeling model. Because of the great influence of fracture on permeability, the fracture distribution model should be established first, and the permeability model should be established with fracture distribution model as secondary variable, which improves the practicability of permeability model.