复杂碳酸盐岩储层裂缝预测方法对比性研究

THE COMPARATIVE ANALYSIS OF DIFFERENT METHODS FOR FRACTURE PREDICTION IN COMPLEX CARBONATE ROCK RESERVOIR

围绕着复杂碳酸盐岩储层裂缝的预测方法,以普光地区嘉陵江组为例,在统计研究区裂缝发育规律的基础上,分别利用构造曲率法、纵波宽方位各向异性法和有限元法对裂缝进行预测,比较各个方法预测结果和适用条件。对比结果表明:曲率法基于几何学理论,可以定性的分析裂缝发育强度,无法预测裂缝方位,该方法适用于基础资料较少、构造简单、褶皱发育的地区;纵波宽方位各向异性法是地球物理法预测裂缝的首选方法,可以直接反映有效裂缝的方位和密度,但是该方法适用于倾斜裂缝和高角度裂缝发育区,对地震资料质量和处理要求较高;有限元数值模拟法从正演角度再现了裂缝形成过程,计算分析裂缝的发育强度和方位,该方法需要对研究区裂缝形成机理认识充分,预测结果的精度取决于模型的精细程度。

Taking Jialingjiang formation in Puguang area as an example, with the fractures development law drawn in the area as a basis, the structural curvature method, S-wave wide azimuth anisotropy method and finite element method were used in fracture prediction, and the results and application conditions of each method were compared. The results show that the curvature method based on the geometry theory could be used to analyze the intensity of fracture development but not the azimuth. It fits in the area with fewer data, simple structure and folds. The S-wave wide azimuth anisotropy method is a preferred geophysics method, which could identify the azimuth and development density of the fracture; however, this method only fits in the area with dipping or high-angle fracture and requires a high quality of seismic data; The finite element method （FEM） could reappear the forming process of fractures in the way of forward and calculate the development intensity and azimuth, but it requires a good understanding of the fracture formation mechanism in the study area, and the accuracy of the prediction results depends on the precision of the model.