吐─哈盆地丘陵油田裂缝定量预测探讨

THE RESEARCH ON QUANTITATIVE PREDICTION OF FRACTURE IN QIULING OIL FIELD, TUHA BASIN

裂缝油藏非常复杂和难以评价，本文从岩石脆性变形和递进变形的理论出发，从理论上指出了对裂缝发育程度进行定量预测的可能性，井尝试着在露头和岩芯裂缝资料的基础上，以脆性岩石的裂缝密度取决于岩石应变量为假设前提，通过构造曲率的定量分析、岩石弹性应变能的数值模拟计算，以及裂缝和断层的关系分析几方面相结合的方法，定量估算丘陵油田不同构造部位裂缝的发育程度。预测结果表明，丘陵油区裂缝发育程度总体有如下特征：裂缝密度总体西部相对较高，东部相对较低；中部较高，南北两侧较低。陵２４、２５井的预测结果和实际资料基本吻合。同时，对预测结果的可靠性作了初步评价。

As oil exploration and technique development progressed rapidly, fractured reservoirs play more and more important role in oil and gas production, and the knowledge about fracture permeability of liquid becomes more clear. Fractured reservoir is very complex and very difficult to be evaluated. There are many obstacles in the quantitative prediction of fractured reservoir, mainly because of highly anisotropic distribution, complicated origin, and multiple-staged development of the fractures. According to the theory of brittle fracturing and progressive deformation of rocks, this paper indicates the possibility of quantitative prediction of fracture development theoretically. Based on outcrop and core fracture data, taking that the fracture density in rocks is determined by the strain as the premise, after structure curvature analysis, theoretical numerical calculation of elastic strain energy, and analysis of falt-fracture relationship, the fracture density is estimated quantitatively in Qiuling oil field. The result of prediction shows that the fracture density in the west and central parts is more developed than that in the east, north and south flanks in Qiuling oil field. The predicted value of fracture density almost coincides with the measured value in well No. 24 and 25. Furthermore, the reliability of the prediction result is evaluated preliminarily.